Illuminate/Database/Eloquent/MassAssignmentException with message 'Add [name] to fillable property to allow mass assignment on [App/Role].' code example

Example: "Illuminate\Database\Eloquent\MassAssignmentException"

//Laravel provides by default a protection against mass assignment security issues. 
//That's why you have to manually define which fields could be "mass assigned" :
class User extends Model
{
    protected $fillable = ['username', 'email', 'password'];
}