User on Element Android is unable to accept my verification request

### Steps to reproduce

1. Where are you starting? What can you see?

From my iOS app I've sent a verification request to @sebastianr:matrix.org.
2. What do you click?
I clicked their username and then verify. I don't receive any error messages when doing this, it just says it's waiting for the other participant:

### What happened?

### What did you expect?
I expected to complete the verification process.
### What happened?
They received the request but nothing happens when they click accept. We both had good connection at the time. Verification request just stays stuck in a loop.

### Your phone model

iPhone 11 Pro

### Operating system version

iOS 14.8

### Application version and app store

Element version 1.5.4

### Homeserver

vector.modular.im

### Have you submitted a rageshake?

Yes