diff --git a/controllers/auth/auth.js b/controllers/auth/auth.js
index 1519b58..9dd5806 100644
--- a/controllers/auth/auth.js
+++ b/controllers/auth/auth.js
@@ -31,6 +31,15 @@ export const registerAdmin = async (req, res) => {
     return response(400, null, "Password is required!", res);
   }
 
+  if (PASSWORD.length < 8) {
+    return response(
+      400,
+      null,
+      "Password must be at least 8 characters long!",
+      res
+    );
+  }
+
   if (!CONFIRM_PASSWORD) {
     return response(400, null, "Confirm Password is required!", res);
   }
@@ -63,6 +72,11 @@ export const registerAdmin = async (req, res) => {
   } catch (error) {
     console.log(error);
 
+    if (error.name === "SequelizeValidationError") {
+      const validationErrors = error.errors.map((err) => err.message);
+      return response(400, null, validationErrors.join("; "), res);
+    }
+
     if (error.name === "SequelizeUniqueConstraintError") {
       return response(400, null, "Email already registered!", res);
     }
@@ -90,6 +104,15 @@ export const registerTeacher = async (req, res) => {
     return response(400, null, "Password is required!", res);
   }
 
+  if (PASSWORD.length < 8) {
+    return response(
+      400,
+      null,
+      "Password must be at least 8 characters long!",
+      res
+    );
+  }
+
   if (!CONFIRM_PASSWORD) {
     return response(400, null, "Confirm Password is required!", res);
   }
@@ -272,21 +295,31 @@ export const registerTeacher = async (req, res) => {
 
     response(200, null, "Teacher registered! Please verify your email.", res);
   } catch (error) {
-    console.log(error);
     await transaction.rollback();
 
-    if (error.name === "SequelizeUniqueConstraintError") {
-      const field = error.original.sqlMessage.match(/for key '(.+)'/)[1];
+    if (error.name === "SequelizeValidationError") {
+      const validationErrors = error.errors.map((err) => err.message);
+      return response(400, null, validationErrors.join("; "), res);
+    }
 
-      if (field === "teacher_unique_nip") {
+    if (error.name === "SequelizeUniqueConstraintError") {
+      const tableMatch =
+        error.original.sqlMessage.match(/for key '(.+)\.(.+)'/);
+      const tableName = tableMatch ? tableMatch[1] : null;
+      const constraintName = tableMatch ? tableMatch[2] : null;
+
+      if (tableName === "users" && constraintName === "user_unique_email") {
+        return response(400, null, "Email already registered!", res);
+      }
+
+      if (tableName === "teacher" && constraintName === "teacher_unique_nip") {
         return response(400, null, "NIP already registered!", res);
       }
 
-      if (field === "user_unique_email") {
-        return response(400, null, "Email already registered!", res);
-      }
+      return response(400, null, "Unique constraint violation!", res);
     }
 
+    console.error(error);
     response(500, null, "Internal Server Error", res);
   }
 };
@@ -310,6 +343,15 @@ export const registerStudent = async (req, res) => {
     return response(400, null, "Password is required!", res);
   }
 
+  if (PASSWORD.length < 8) {
+    return response(
+      400,
+      null,
+      "Password must be at least 8 characters long!",
+      res
+    );
+  }
+
   if (!CONFIRM_PASSWORD) {
     return response(400, null, "Confirm Password is required!", res);
   }
@@ -492,21 +534,31 @@ export const registerStudent = async (req, res) => {
 
     response(200, null, "Student registered! Please verify your email.", res);
   } catch (error) {
-    console.log(error);
     await transaction.rollback();
 
-    if (error.name === "SequelizeUniqueConstraintError") {
-      const field = error.original.sqlMessage.match(/for key '(.+)'/)[1];
+    if (error.name === "SequelizeValidationError") {
+      const validationErrors = error.errors.map((err) => err.message);
+      return response(400, null, validationErrors.join("; "), res);
+    }
 
-      if (field === "student_unique_nisn") {
+    if (error.name === "SequelizeUniqueConstraintError") {
+      const tableMatch =
+        error.original.sqlMessage.match(/for key '(.+)\.(.+)'/);
+      const tableName = tableMatch ? tableMatch[1] : null;
+      const constraintName = tableMatch ? tableMatch[2] : null;
+
+      if (tableName === "users" && constraintName === "user_unique_email") {
+        return response(400, null, "Email already registered!", res);
+      }
+
+      if (tableName === "student" && constraintName === "student_unique_nisn") {
         return response(400, null, "NISN already registered!", res);
       }
 
-      if (field === "user_unique_email") {
-        return response(400, null, "Email already registered!", res);
-      }
+      return response(400, null, "Unique constraint violation!", res);
     }
 
+    console.error(error);
     response(500, null, "Internal Server Error", res);
   }
 };
@@ -545,6 +597,15 @@ export const registerTeacherForAdmin = async (req, res) => {
     return response(400, null, "Password is required!", res);
   }
 
+  if (PASSWORD.length < 8) {
+    return response(
+      400,
+      null,
+      "Password must be at least 8 characters long!",
+      res
+    );
+  }
+
   if (!CONFIRM_PASSWORD) {
     return response(400, null, "Confirm Password is required!", res);
   }
@@ -594,16 +655,26 @@ export const registerTeacherForAdmin = async (req, res) => {
     console.log(error);
     await transaction.rollback();
 
-    if (error.name === "SequelizeUniqueConstraintError") {
-      const field = error.original.sqlMessage.match(/for key '(.+)'/)[1];
+    if (error.name === "SequelizeValidationError") {
+      const validationErrors = error.errors.map((err) => err.message);
+      return response(400, null, validationErrors.join("; "), res);
+    }
 
-      if (field === "teacher_unique_nip") {
+    if (error.name === "SequelizeUniqueConstraintError") {
+      const tableMatch =
+        error.original.sqlMessage.match(/for key '(.+)\.(.+)'/);
+      const tableName = tableMatch ? tableMatch[1] : null;
+      const constraintName = tableMatch ? tableMatch[2] : null;
+
+      if (tableName === "users" && constraintName === "user_unique_email") {
+        return response(400, null, "Email already registered!", res);
+      }
+
+      if (tableName === "teacher" && constraintName === "teacher_unique_nip") {
         return response(400, null, "NIP already registered!", res);
       }
 
-      if (field === "user_unique_email") {
-        return response(400, null, "Email already registered!", res);
-      }
+      return response(400, null, "Unique constraint violation!", res);
     }
 
     response(500, null, "Internal Server Error", res);
@@ -667,16 +738,26 @@ export const registerStudentForAdminAndTeacher = async (req, res) => {
 
     await transaction.rollback();
 
-    if (error.name === "SequelizeUniqueConstraintError") {
-      const field = error.original.sqlMessage.match(/for key '(.+)'/)[1];
+    if (error.name === "SequelizeValidationError") {
+      const validationErrors = error.errors.map((err) => err.message);
+      return response(400, null, validationErrors.join("; "), res);
+    }
 
-      if (field === "student_unique_nisn") {
+    if (error.name === "SequelizeUniqueConstraintError") {
+      const tableMatch =
+        error.original.sqlMessage.match(/for key '(.+)\.(.+)'/);
+      const tableName = tableMatch ? tableMatch[1] : null;
+      const constraintName = tableMatch ? tableMatch[2] : null;
+
+      if (tableName === "users" && constraintName === "user_unique_email") {
+        return response(400, null, "Email already registered!", res);
+      }
+
+      if (tableName === "student" && constraintName === "student_unique_nisn") {
         return response(400, null, "NISN already registered!", res);
       }
 
-      if (field === "user_unique_email") {
-        return response(400, null, "Email already registered!", res);
-      }
+      return response(400, null, "Unique constraint violation!", res);
     }
 
     response(500, null, "Internal Server Error", res);
@@ -844,6 +925,12 @@ export const registerStudentCSV = async (req, res) => {
   } catch (error) {
     console.error(error);
     await transaction.rollback();
+
+    if (error.name === "SequelizeValidationError") {
+      const validationErrors = error.errors.map((err) => err.message);
+      return response(400, null, validationErrors.join("; "), res);
+    }
+
     response(500, null, "Internal Server Error", res);
   }
 };
@@ -1196,6 +1283,15 @@ export const resetPassword = async (req, res) => {
     return response(400, null, "New password is required!", res);
   }
 
+  if (NEW_PASSWORD.length < 8) {
+    return response(
+      400,
+      null,
+      "Password must be at least 8 characters long!",
+      res
+    );
+  }
+
   if (!CONFIRM_NEW_PASSWORD) {
     return response(400, null, "Confirm new password is required!", res);
   }
diff --git a/controllers/usersControllers/user.js b/controllers/usersControllers/user.js
index 810c1e8..fcaccf6 100644
--- a/controllers/usersControllers/user.js
+++ b/controllers/usersControllers/user.js
@@ -523,6 +523,32 @@ export const updateUserById = async (req, res) => {
   } catch (error) {
     clearFileBuffers({ PICTURE });
     await transaction.rollback();
+
+    if (error.name === "SequelizeValidationError") {
+      const validationErrors = error.errors.map((err) => err.message);
+      return response(400, null, validationErrors.join("; "), res);
+    }
+
+    if (error.name === "SequelizeUniqueConstraintError") {
+      const tableMatch =
+        error.original.sqlMessage.match(/for key '(.+)\.(.+)'/);
+      const tableName = tableMatch ? tableMatch[1] : null;
+      const constraintName = tableMatch ? tableMatch[2] : null;
+
+      if (tableName === "users" && constraintName === "user_unique_email") {
+        return response(400, null, "Email already registered!", res);
+      }
+
+      if (tableName === "student" && constraintName === "student_unique_nisn") {
+        return response(400, null, "NISN already registered!", res);
+      }
+
+      if (tableName === "teacher" && constraintName === "teacher_unique_nip") {
+        return response(400, null, "NIP already registered!", res);
+      }
+
+      return response(400, null, "Unique constraint violation!", res);
+    }
     console.log(error);
     return response(500, null, "Internal Server Error", res);
   }
@@ -537,6 +563,15 @@ export const updateUserPasswordById = async (req, res) => {
       return response(400, null, "All fields must be filled.", res);
     }
 
+    if (PASSWORD.length < 8) {
+      return response(
+        400,
+        null,
+        "Password must be at least 8 characters long!",
+        res
+      );
+    }
+
     if (PASSWORD !== CONFIRM_PASSWORD) {
       return response(
         400,
diff --git a/models/usersModels/studentModel.js b/models/usersModels/studentModel.js
index 03744b7..257bb38 100644
--- a/models/usersModels/studentModel.js
+++ b/models/usersModels/studentModel.js
@@ -38,6 +38,12 @@ const StudentModel = (DataTypes) => {
         unique: true,
         validate: {
           notEmpty: true,
+          is10Digits(value) {
+            const stringValue = value.toString();
+            if (stringValue.length !== 10) {
+              throw new Error("NISN must be exactly 10 digits long");
+            }
+          },
         },
       },
     },
diff --git a/models/usersModels/teacherModel.js b/models/usersModels/teacherModel.js
index 0c63c94..d96102d 100644
--- a/models/usersModels/teacherModel.js
+++ b/models/usersModels/teacherModel.js
@@ -30,6 +30,12 @@ const TeacherModel = (DataTypes) => {
         unique: true,
         validate: {
           notEmpty: true,
+          is16Digits(value) {
+            const stringValue = value.toString();
+            if (stringValue.length !== 16) {
+              throw new Error("NIP must be exactly 16 digits long");
+            }
+          },
         },
       },
     },
diff --git a/models/usersModels/userModel.js b/models/usersModels/userModel.js
index eaf02c6..1bf27dc 100644
--- a/models/usersModels/userModel.js
+++ b/models/usersModels/userModel.js
@@ -20,19 +20,28 @@ const UserModel = (DataTypes) => {
           notEmpty: true,
         },
       },
+      PASSWORD: {
+        type: DataTypes.STRING(100),
+        allowNull: false,
+        validate: {
+          notEmpty: true,
+          len: {
+            args: [8, 100],
+            msg: "Password must be at least 8 characters long",
+          },
+        },
+      },
       EMAIL: {
         type: DataTypes.STRING(100),
         allowNull: false,
         unique: true,
         validate: {
           notEmpty: true,
-          isEmail: true,
+          isEmail: {
+            msg: "Email must be a valid email address",
+          },
         },
       },
-      PASSWORD: {
-        type: DataTypes.STRING(100),
-        allowNull: false,
-      },
       ROLE: {
         type: DataTypes.STRING(100),
         allowNull: true,