[Solved]Cakephp 3.7.1 route cache error

1

I am getting:
Error: [InvalidArgumentException] The “cake_routes” cache configuration does not exist.

Have searched but all I saw was:
https://github.com/cakephp/debug_kit/issues/627 outdated

I remembered an earlier version I changed:

add(new RoutingMiddleware($this, '_cake_routes_'));

to

 ->add(new RoutingMiddleware($this));

It works now, I still don’t know why top line does not work.