Illuminate\Contracts\Container\BindingResolutionException

Unresolvable dependency resolving [Parameter #0 [ <required> $user ]] in class App\Mail\ThanksForSubmittingMail

    {

        $message = "Unresolvable dependency resolving [$parameter] in class {$parameter->getDeclaringClass()->getName()}";

        throw new BindingResolutionException($message);

    }

Solution

my constructor did not contain my user model. i had the following:
public function __construct($user)
    {
        $this->user = $user;
    }

and changed it to:
  public function __construct(User $user)
    {
        $this->user = $user;
    }
That fixed it for me