I’m also experiencing this issue on a brand new IC4.
Using a Pixel 5 on Android and have reset both my phone and the bike to no avail. So frustrating that I might just return the bike.
Funny thing is I had a Saris H3 I just sold bc I never used it. Was finicky hooking up my MTB and the freehub was ridiculously loud. Little did I know that the fixed gear on the IC4 is significantly less pleasant. And I essentially just downgraded. Was hoping having a dedicated exercise bike would provide a bit less hassle than changing my bike over and messing with the derailleur (was always making noise), but without smooth connectivity to Zwift it’s driving me mad.
Anywho… Have you gotten the IC4 working with your Android device? Any hope?