Rejecting incoming call doesn't end call

Steps to reproduce

1. initiate private call to another nextcloud talk user
2. reject incoming call, by pressing red button on call notification screen

Expected behaviour

I would expect that when user decline my incoming call, my call request should be terminated.

Actual behaviour

When user decline my incoming call, I as an initiator of this call still see the "Waiting for other paticipants to join the call" screen.
Also I noticed in log that when I push the decline button in mobile application, it sends a DELETE request (probably on malformed uri), that results with 404. See log line attached bellow I believe that there is a room id missing in the request uri.

Device information

Device: Honor 10 Lite

Android version: 10

Talk version: 11.1.0

Server information

Nextcloud version: 20.0.10

Talk version: 10.0.8

Custom Signaling server configured: yes

Custom TURN server configured: yes

Custom STUN server configured: yes

Server log (data/nextcloud.log)

"DELETE /ocs/v2.php/apps/spreed/api/v1/room//participants/active HTTP/2.0" 404 286 "-" "Mozilla/5.0 (Android) Nextcloud-Talk v11.1.0" "-"

Start by tracing the Android request that handles rejecting an incoming call and compare it with the logged DELETE endpoint /ocs/v2.php/apps/spreed/api/v1/room//participants/active. Done means the rejection targets the correct room and the caller no longer remains on the waiting screen; the issue does not name a source file or test.