Multiple password in Laravel validateCredentials method

Hi I am using Laravel to create my web app. I have a table named buyerData in which I have two columns that are designed to store Password. Their names are,

1- Password 2- buyerData_fb_password

Now the issue I am facing the laravel be default thinks the column which contains password in your table is named as "Password". But in my case I have another column. How can I tweak the laravel framework to accept both columns as password, depends upon the column that is used at a given time.

For example the below code is working fine because it is using the default column "password".

if (Auth::guard('buyer')->attempt(['buyerData_primaryEmail' => $userEmail, 
'password' => $unhashPass]));

But the below code is not working as expected because its use the other column name "buyerData_fb_password" and shows the error. (Shown below after code).

if (Auth::guard('buyer')->attempt(['buyerData_primaryEmail' => $userEmail, 
'buyerData_fb_password' => $unhashPass])); 

Shows this error

I tweaked the validateCredentials() function a little bit and made the following changes,

public function validateCredentials(UserContract $user, array $credentials) {

if (isset($credentials['password']))
 {
      $plain = $credentials['password'];
}

else
{

     $plain = $credentials['buyerData_fb_password'];
}

return $this->hasher->check($plain, $user->getAuthPassword());

}

After this the code is working with "buyerData_fb_password" and login is successfull but it if I visit any other page in my website then it shows that the user is not login. Any suggestion? Thanks

via Chebli Mohamed