Bluetooth pairing works on the principal of one-to-one pairing, so once one app is connected, the trainer or sensor does everything it can to stay connected to that app. So we get complaints that "it works fine in Zwift" and they get complaints "it works fine in FulGaz" or whatever other app someone has been using.
To fix your problem
Make sure Zwift (or any other app) is no longer connected to any trainer or sensor you want to connect to FulGaz
- Quit Zwift
- Quit FulGaz
- For iPhones and iPads, quit bluetooth and restart it. For Apple TV, unplug it.
- Restart FulGaz and connect
FulGaz on multiple devices
Remember, the app causing the problem could be FulGaz. for example, if you have FulGaz installed on an iPad and an Apple TV, make sure you've deselected your sensors and quit FulGaz on the iPad before trying to connect to the Apple TV.
Utility apps like the Wahoo fitness app or Tacx Utility
Make sure you have quit these apps before trying to connect to FulGaz. They should not be running or connected to your trainer or sensors when using FulGaz.