Hotspot connection from iPhone to iPhone closes regularly…

The following problem: Hotspot on iPhone SE, connection to it from an iPad remains permanently stable, from my iPhone 13 mini it breaks off and after a while the hotspot appears to be closed/invisible.

A network settings reset was carried out on both devices (the SE with hotspot and the 13 mini, which connects). If the 13 mini connects to another WLAN, the connection remains stable...

Any Idea?

Thanks for any help…