Run php artisan route:cache and then php artisan route:clear.
Then, for as long as you're in development mode, don't cache routes or configuration files. Only in production. Caching the routes above, should fetch a fresh copy of routes, and then we'll just clear them out again.
Restarting your local server will also help
After running the route:clear command, double check that there is no file in the bootstrap/cache directory, named routes.php.