Recently, I have to migrate some personal projects from Laravel 7.X to the latest Laravel version 8. After spending a long time making some testing in order to get rid of this issue (First, I thought I was missing any resources or namespace in my code), It appears that Laravel developers have decided to slightly modify the routing system. The synt ax of binding the string url to the string Controller is not recommended anymore, and this is because in the Service Routing providers, the $namespace attribute is commented by default For information, The $namespace is the key to how Laravel interprets your routes . In order to use the new routing system in your web.php or api.php, it is recommended to import the controller class.