Infinite loop of trusting a certificate

### Steps to reproduce

I have a Matrix Synapse server set up on my domain. The domain has an SSL certificate signed by my self-signed CA certificate, **which is set as a trusted root certificate on my mobile device**.

### Outcome

When I try to log in using the mobile app (downloaded from Play Store) and enter the domain name of the Synapse server I get a notification "Could not verify identity of remote server". After clicking "TRUST" the same notification pops up.
The notificaiton contains a SHA256 fingerprint, of which there are two - first I see the first fingerprint, then I press "TRUST" and I see the second one. After pressing "TRUST" on the second notification with the second fingerprint another notification with the first fingerprint shows up and so on...

### Your phone model

Redmi Note 10 Pro

### Operating system version

11 RKQ1.200826.002

### Application version and app store

Cannot go to settings as I'm not logged in (newest version from Google Play Store as of the time of submitting this issue)

### Homeserver

Lastest Synapse Ubuntu package release

### Will you send logs?

No

### Are you willing to provide a PR?

No