A new update with Google Play and Moto G4 phones (maybe only the Plus model) may affect the bluetooth functions of the phone.
Reported on the blog Android Police:
We received a tip today about a strange problem affecting bluetooth on the Moto G4 Play, and it has something to do with Google Play Protect…
What appears to be happening is that Google Play Protect on the Moto G4 Plus (running Nougat 7.0) is mistaking a system app called Bluetooth Share 7.0 for something unsafe. Play Protect then disables the app it and asks if you want it to be removed…
After turning on bluetooth, it seems to have a think for a moment or two before just shutting off.
To fix it, navigate to Settings > Applications > Reset Application Settings you can revert back to the way things were. (Note this will also reset some other settings such as which default app or if you have disabled any apps yourself)
Hope no one sees this themselves!
Source: Android Police