I use element call on my own homeserver. After initiating, the other party does not display the join button

### Steps to reproduce

1. Where are you starting? What can you see?
I still use the call service of call.element.io, but every time I initiate a call, other people in the room can only see that the call was started but cannot join.
I'm not very familiar with Android, so can anyone give me some advice, because I don't see any error logs
2. What do you click?
just send a call in the room
3. More steps…

### Outcome

#### What did you expect?
Reciver can see the join button and join the call

#### What happened instead?

### Your phone model

Simulator API 33

### Operating system version

_No response_

### Application version and app store

_No response_

### Homeserver

_No response_

### Will you send logs?

No

### Are you willing to provide a PR?

No