AntennaPod does not recognise WLAN

App version: 2.2.1
Android version: 10
Device model: Nokia 7.1

I have been using AntennaPod for at least a year without any problems. Recently I have this error:
I have set AntennaPod to download podcasts only when the smartphone is connected to a WLAN. Now I try to save a podcast, but AntennaPod asks me if I agree (once) that the download is done via “mobile data”. Yet WLAN is demonstrably available. (The other apps access it without any problems). Switching WLAN off and on again does not help either.
However, as I discovered by comparing the data volume used, the download is carried out via WLAN…