Accessor method not call properly in laravel

In mycase when i set column name like USERDATA in mysql DB and my user model code look like below.

.....
....

public function getUserData($value){

    if($value != null){
      return  $this->directory.$value;
    }
  }

.......
.......

But I set small letter in DB like userdata. properly call accessor method

How to resolve?

I search many ways but not get any proper solution

via Chebli Mohamed