.htaccess Debug Require expr - apache

Question

I'm trying to allow all requests to a specific url for webhooks to a development platform. Require expr works partially.
This website should only be completly accessible for specifig users. Using
"Require expr %{REQUEST_URI} =~ m#^.*webhook.*$#" I'm trying to get this working. I also tried LocationMatch, which won't work for other circumstances.
AuthType Basic
AuthName "Please enter password"
require group xy yz
<IfModule mod_authz_core.c>
<RequireAny>
Require expr %{REQUEST_URI} =~ m#^.*webhook.*$#
...
</RequireAny>
</IfModule>
If I call the url example.com/webhook/xyz/ the request is not accepted and returns the realm login.
The log:
[Mon May 27 20:15:58.972495 2019] [authz_core:debug] [pid 15344] mod_authz_core.c(820): [client xxx.xxx.xxx.xxx:50341] AH01626: authorization result of Require group xy yz: denied (no authenticated user yet)
[Mon May 27 20:15:58.972519 2019] [authz_core:debug] [pid 15344] mod_authz_core.c(820): [client xxx.xxx.xxx.xxx:50341] AH01626: authorization result of Require expr %{REQUEST_URI} =~ m#^.*webhook.*$#: granted
[Mon May 27 20:15:58.972526 2019] [authz_core:debug] [pid 15344] mod_authz_core.c(820): [client xxx.xxx.xxx.xxx:50341] AH01626: authorization result of <RequireAny>: granted
[Mon May 27 20:15:58.972813 2019] [authz_core:debug] [pid 15344] mod_authz_core.c(820): [client xxx.xxx.xxx.xxx:50341] AH01626: authorization result of Require group xy yz: denied (no authenticated user yet)
[Mon May 27 20:15:58.972824 2019] [authz_core:debug] [pid 15344] mod_authz_core.c(820): [client xxx.xxx.xxx.xxx:50341] AH01626: authorization result of Require expr %{REQUEST_URI} =~ m#^.*webhook.*$#: denied
[Mon May 27 20:15:58.973126 2019] [authz_core:debug] [pid 15344] mod_authz_core.c(820): [client xxx.xxx.xxx.xxx:50341] AH01626: authorization result of <RequireAny>: denied (no authenticated user yet)
[Mon May 27 20:15:58.973154 2019] [auth_basic:error] [pid 15344] [client xxx.xxx.xxx.xxx.47:50341] AH01614: client used wrong authentication scheme: /router.php
And I really don't know why he is denying this requests after it was granted. Maybe a redirect? PHP says $_SERVER['REQUEST_URI'] is still the same after I tried to grant my ip address. So I guess it's not a redirect issue. Any idea what can cause that problem or how to debug this?