When you have a wifi mesh system with several AP’s,
it is probably hopping between two (or more) AP’s very often → Homey 2023 has a complete different wifi implementation than the earlier model.
I’m guessing the app can’t handle this very well, while, like you wrote, the connected devices do stay connected w/o any issue.
Try to let Homey use a fixed AP, by using MAC address filtering, or Band Steering, and/or lower the transmit power on distant AP’s for instance.