Laravel sending email call_user_func() error

I am trying to send email in laravel for which I am using the mail::send functon.

This is my code

$data = [
          'title'=>'Some Title',
          'content'=>'Content',
          'email'=> 'email',
          'password'=>'password',
          'remarks'=>'remarks'
      ];

      Mail::send('admin.mails.activate', $data, ['user'=>$user], function ($message) use ($user) {
          $message->to($user->email, $user->name)->subject('Account Activation Email')->from('support@webmail.com');
      });

I am trying to pass the $data variable to the view file and $user variable to the callback function so that I could use user's email to send email. But it is giving me this error.

    call_user_func() expects parameter 1 to be a valid callback, array must have exactly two members 

via Chebli Mohamed