Can't start call in Talk

[uan]

I installed Signaling server as it described here . When I add High-performance backend in Talk settings I see:
OK: Running version: b89e017ae480dda0ec7391dfa67465276a0e3748
But when I go to some conversation message “Establishing signaling connection is taking longer than expected …” begins to appear.
And when I press “Start call” circle spinning and nothing happens…
In NC log i see such errors:
{"reqId":"aPHSEEWFIFwwd9ohrJrN","level":3,"time":"2021-01-27T07:50:34+00:00","remoteAddr":"192.168.1.1","user":"--","app":"spreed","method":"POST","url":"/ocs/v2.php/apps/spreed/api/v1/chat/iybptuh3","message":{"Exception":"GuzzleHttp\\Exception\\ClientException","Message":"Client error: POST https://signaling.mydomain.tld/api/v1/room/iybptuh3resulted in a403 Forbidden response:\nAuthentication check failed\n\n","Code":403,"Trace":[{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/guzzle/src/Middleware.php","line":65,"function":"create","class":"GuzzleHttp\\Exception\\RequestException","type":"::"},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/promises/src/Promise.php","line":203,"function":"GuzzleHttp\\{closure}","class":"GuzzleHttp\\Middleware","type":"::","args":["*** sensitive parameters replaced ***"]},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/promises/src/Promise.php","line":156,"function":"callHandler","class":"GuzzleHttp\\Promise\\Promise","type":"::"},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/promises/src/TaskQueue.php","line":47,"function":"GuzzleHttp\\Promise\\{closure}","class":"GuzzleHttp\\Promise\\Promise","type":"::","args":["*** sensitive parameters replaced ***"]},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/promises/src/Promise.php","line":246,"function":"run","class":"GuzzleHttp\\Promise\\TaskQueue","type":"->"},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/promises/src/Promise.php","line":223,"function":"invokeWaitFn","class":"GuzzleHttp\\Promise\\Promise","type":"->"},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/promises/src/Promise.php","line":267,"function":"waitIfPending","class":"GuzzleHttp\\Promise\\Promise","type":"->"},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/promises/src/Promise.php","line":225,"function":"invokeWaitList","class":"GuzzleHttp\\Promise\\Promise","type":"->"},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/promises/src/Promise.php","line":62,"function":"waitIfPending","class":"GuzzleHttp\\Promise\\Promise","type":"->"},{"file":"/var/www/nextcloud/3rdparty/guzzlehttp/guzzle/src/Client.php","line":183,"function":"wait","class":"GuzzleHttp\\Promise\\Promise","type":"->"},{"file":"/var/www/nextcloud/lib/private/Http/Client/Client.php","line":304,"function":"request","class":"GuzzleHttp\\Client","type":"->"},{"file":"/var/www/nextcloud/apps2/spreed/lib/Signaling/BackendNotifier.php","line":80,"function":"post","class":"OC\\Http\\Client\\Client","type":"->"},{"file":"/var/www/nextcloud/apps2/spreed/lib/Signaling/BackendNotifier.php","line":130,"function":"doRequest","class":"OCA\\Talk\\Signaling\\BackendNotifier","type":"->"},{"file":"/var/www/nextcloud/apps2/spreed/lib/Signaling/BackendNotifier.php","line":334,"function":"backendRequest","class":"OCA\\Talk\\Signaling\\BackendNotifier","type":"->"},{"file":"/var/www/nextcloud/apps2/spreed/lib/Signaling/Listener.php","line":247,"function":"sendRoomMessage","class":"OCA\\Talk\\Signaling\\BackendNotifier","type":"->"},{"file":"/var/www/nextcloud/3rdparty/symfony/event-dispatcher/EventDispatcher.php","line":251,"function":"OCA\\Talk\\Signaling\\{closure}","class":"OCA\\Talk\\Signaling\\Listener","type":"::","args":["*** sensitive parameters replaced ***"]},{"file":"/var/www/nextcloud/3rdparty/symfony/event-dispatcher/EventDispatcher.php","line":73,"function":"callListeners","class":"Symfony\\Component\\EventDispatcher\\EventDispatcher","type":"->"},{"file":"/var/www/nextcloud/lib/private/EventDispatcher/EventDispatcher.php","line":86,"function":"dispatch","class":"Symfony\\Component\\EventDispatcher\\EventDispatcher","type":"->"},{"file":"/var/www/nextcloud/apps2/spreed/lib/Chat/ChatManager.php","line":217,"function":"dispatch","class":"OC\\EventDispatcher\\EventDispatcher","type":"->"},{"file":"/var/www/nextcloud/apps2/spreed/lib/Controller/ChatController.php","line":195,"function":"sendMessage","class":"OCA\\Talk\\Chat\\ChatManager","type":"->"},{"file":"/var/www/nextcloud/lib/private/AppFramework/Http/Dispatcher.php","line":169,"function":"sendMessage","class":"OCA\\Talk\\Controller\\ChatController","type":"->"},{"file":"/var/www/nextcloud/lib/private/AppFramework/Http/Dispatcher.php","line":100,"function":"executeController","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->"},{"file":"/var/www/nextcloud/lib/private/AppFramework/App.php","line":152,"function":"dispatch","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->"},{"file":"/var/www/nextcloud/lib/private/Route/Router.php","line":309,"function":"main","class":"OC\\AppFramework\\App","type":"::"},{"file":"/var/www/nextcloud/ocs/v1.php","line":88,"function":"match","class":"OC\\Route\\Router","type":"->"},{"file":"/var/www/nextcloud/ocs/v2.php","line":24,"args":["/var/www/nextcloud/ocs/v1.php"],"function":"require_once"}],"File":"/var/www/nextcloud/3rdparty/guzzlehttp/guzzle/src/Exception/RequestException.php","Line":113,"CustomMessage":"Failed to send message to signaling server"},"userAgent":"Mozilla/5.0 (Windows NT 6.1; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/87.0.4280.141 Safari/537.36","version":"20.0.5.2","id":"60111b4b5a6b8"}
But these errors appears only when I cancel calling on android app.
In Chrome DevTools when I go to some conversation I see requests to wss://signaling.mydomain.tld/spreed with such answering message:
{“id”:“1”,“type”:“error”,“error”:{“code”:“invalid_request”,“message”:“The request could not be authenticated.”}}
and in console i see such errors:

[uan]

I don’t know how it’s related but setting
[backend]
allowall=false
in server.conf resolved the problem.
I think it has something to do with OAuth2/OIDC (I use Social login plugin)