Try to run php artisan migrate:fresh - that will delete all of your existing tables and create them again. If the error still exists then you have more than one migration for creating users table. Delete one of them and you should be good to go.
According to default eloquent conventions: eloquent model tries to fetch data from the pluralized model name ( if you have table called currency, by default it will try to fetch data from currencies table ).
So, to manually specify table name you have to add $table property to your model like so:
If you don't use your database on production, just freely fresh all database by using php artisan migrate:fresh.
If you keep all your database structure in migrations then php artisan migrate:fresh will set everything back after deleting all tables. And you can identify your problem this way faster.