Error creating social authorization?

Question

API

Good morning, I do everything according to the article https://laravel-news.ru/blog/tutorials/socialite-login, the socialite package is pre-installed and configured, the tables are made, when authorizing through VKontakte, it gives the following:
ErrorException in Model.php line 3517:
Use of undefined constant 'user_social_account' - assumed ''user_social_account''
What is the reason I don't understand?(

Answer 1

Use of undefined constant 'user_social_account' - assumed ''user_social_account''

Obviously this is a mistake. You need to see the code where it is used.
But apparently they just copied and pasted the code from the article, and there are crooked quotes ...