No TURN server and no fallback STUN server

When we unload the application and place a call on it, immediately upon receiving a call, application requests a list of turn servers from the server, but without waiting for an answer continues to work without turn / stun.
Log:
15: 00: 47.702188 + 0200 Riot [MXHTTPClient] # 1 - GET _matrix / client / r0 / voip / turnServer
15: 00: 48.083760 + 0200 Riot [MXCall] No TURN server and no fallback STUN server
15: 00: 48.162102 + 0200 Riot [MXHTTPClient] # 1 - GET _matrix / client / r0 / voip / turnServer completed in 459ms

Steps to reproduce the behavior:
1. Unload Element app
2. Place a call on that phone

**Expected behavior**
Wait for a TURN\STUN server to answer

**Smartphone (please complete the following information):**
- OS: iOS 14

Start by reproducing the incoming-call flow after unloading the iOS app and compare the TURN request and call logs shown in the issue. Trace the call setup around the _matrix/client/r0/voip/turnServer request; done means the call waits for the TURN/STUN response instead of proceeding without either server.

Written by the indexing model from the issue text.