HAProxy stick on url_param(room)

Hello!

I am currently setting up HAProxy for multiple Jitsi shards. I really skimmed every topic in this forum, but I dont know why it isnt working.

This is my config:

frontend haproxynode
 bind *:80
 bind *:443 ssl crt /etc/letsencrypt/live/mydomain/mydomain.pem
 http-request redirect scheme https unless { ssl_fc }
 option forwardfor
 default_backend backendnodes

backend backendnodes
  balance leastconn
  mode http
  stick-table type string len 256 size 200k expire 120m
  stick on url_param(room) table backendnodes
  server shard1 jitsi1dev.mydomain:443 maxconn 8192 check ssl verify none
  server shard2 jitsi2dev.mydomain:443 maxconn 8192 check ssl verify none

The weird thing is: It works when I join mydomain.com/test?room=test, then it routes it correctly!

This is a non-profit system for not digitalized schools here, any help would help me a lot!

Thank you in advance.