Failed to use my own Cookie model in tracker config file

I have a Cookie model and replaced it with the default cookie model.
Here is my code in `config/tracker.php`:

`'cookie_model' => 'App\Cookie',`

When I run this code, I got this error:


Start with the `cookie_model` setting in `config/tracker.php` and reproduce the failure using `App\Cookie` instead of the default cookie model. Investigate the error shown in the attached screenshot and verify that the configured custom model is accepted without the reported error.

Written by the indexing model from the issue text.