Firechat off-the-grid "nearby" mode broken in Android app?

https://play.google.com/store/apps/d...arden.firechat

This app should allow ppl to create a mesh network to chat. The "nearby" mode doesn't use internet or any access point. The app allows the devices to communicate with each other by wifi or bluetooth. In addition, it allows relay. For example, if A and B are too far apart for wifi range, C can be in between and create a mesh network of A, B and C.

I have tested this feature with 5 android devices right next to each other. All 5 devices get notification "Firechat users are nearby" But they can't chat in "nearby" room. This has to be a bug with Android app because it works on iPhones using iOS airdrop.

BTW, if android devices connect to the same access point, they can chat in "nearby" room. Can anyone help me?