The website encountered an unexpected error due to installing custom module I have created and installed custom module without additional code[with mymodule.info and mymodule.module].But after I created


  mymodule.links.menu.yml and mymodule.routing.yml i am grtting error like "The website encountered an unexpected error" code mymodule.links.menu.yml


   mymodule.admin_form
     title: Upload IELTS Test Dates
     parent: cedar.admin_index
     weight: 100
     route_name : mymodule.admin_form


and code inside mymodule.routing.yml

 mymodule.settings:
   path: '/admin/config/services/migs'
   defaults:
     _controller: '\Drupal\quotesapi\Controller\MymoduleController::settings'
     _title: 'My module settings'
   requirements:
     _permission: 'administer site configuration'


I checked the watchdog and found a RouteNotFoundException. How do I fix this?
It looks like a simple naming error. Your route name in the links file is:

route_name : mymodule.admin_form


But in your routing.yml you have:

 mymodule.settings:


Update one or the other so they both match, clear the cache, and it should work.