I’m working on a Laravel project and encountered a strange issue when trying to insert a new user into the users table. The error I’m seeing is:

SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '[email protected]' for key 'users_email_unique'

What’s odd is that when I query the database, I can’t find any user with the email “[email protected]”. Here’s a bit more context:

• I’m using a migration to create the users table, and the email column is set to be unique.
• I’ve also used Laravel’s seeder to generate fake data in this table before attempting this insert.

Here’s the migration for the users table:

Schema::create('users', function (Blueprint $table) {
$table->id();
$table->string('name');
$table->string('email')->unique();
$table->string('user_name')->unique()->nullable();
$table->string('phone')->unique()->nullable();
$table->timestamp('email_verified_at')->nullable();
$table->string('password');
$table->rememberToken();
$table->enum('role', ['student', 'teacher', 'admin']);
$table->boolean('is_active')->default(1);
$table->timestamps();
$table->softDeletes();
});

Here’s my validation rules:

 public function rules(): array
    {
        $rules = [
            
            'user_name' => [
                'nullable',
                'string',
                Rule::unique('users', 'user_name'),
            ],
            'email' => [
                'required',
                'email',
                Rule::unique('users', 'email'),
            ],
        ];

        return $rules;
    }

I tried querying the users table directly using Laravel’s

DB::table('users')->where('email', '[email protected]')->first() 

to see if there was already a record with that email. I expected to find either a matching record or no results at all. However, the query returned null, indicating that no user with this email exists, yet the “Duplicate entry” error persists when I attempt to insert a new record.

My Questions:

• Why is Laravel/MySQL throwing a “Duplicate entry” error for an email that appears not to exist in the database?
• How can I troubleshoot or resolve this issue?

I’m really stuck on this and would appreciate any help or pointers!