fetching new messages/ notifications do not work on mobile networks, only wifi

### Steps to reproduce

Since one or two weeks our mobile devices do not notify about new messages while only having access to a mobile network, i.e. LTE or 5G.

If one opens the chat, the new messages are loaded, i.e. they were not received before. So probably it's not the notification which is not working, but the fetching new messages.

As soon as we are on WiFi it works.

It also works with Element X on the same devices.

### Outcome

#### What did you expect?
New messages are fetched automatically and the user is notified.

#### What happened instead?
New messages are only fetched, if the app is opened.

### Your phone model

Pixel 6 and 8a

### Operating system version

15

### Application version and app store

1.6.36

### Homeserver

matrix.org

### Will you send logs?

No

### Are you willing to provide a PR?

No