"SQLSTATE[42S22]: Column not found: 1054 Unknown column 'api_token' in 'where clause'

 This error occurred when passport authentication were installed and while checking the /user route.

This error might cause for the new changes in authentication file, config file & changes in route. So, what worked for me is this:

php artisan config:clear

php artisan config:cache 

php artisan cache:clear