If you're having trouble connecting a new Bluetooth device or staying connected to a previously connected device, it might mean that the Bluetooth cache on your device is broken.
Fortunately, clearing the Bluetooth cache is easy, and that usually solves common connection problems. Here are the steps.
Clear Bluetooth Cache on iPhone or iPad:
1. Open the Settings app and tap on “Bluetooth”.
2. If you're having trouble with a specific device that's already paired, find it in the My devices list and tap the "i" icon next to it, then choose the "forget this device" command.
3. If your problem is with more general bluetooth - for example: you can't pair any new device to it - delete all devices with the "forget all device in my bluetooth list" command (you will need to re-pair them once others later).
4. Reboot your device.
After restarting your iPhone or iPad, the Bluetooth cache will be cleared, and you can re-pair your devices to use them again.
Clear Bluetooth Cache on Android Phone or Tablet:
1. Go to the device's settings feature.
2. Click "Connections", then click "Bluetooth".
3. If you're having trouble with a specific device that's already paired, find it in the Paired Devices list, tap the gear icon next to it, and tap Unpair.
4. If your problem is with more general Bluetooth - eg: you can't pair any new device to it - unpair each Bluetooth device in the list of paired devices (you'll need to pair them again later).
There is also a more comprehensive way to clear the cache via Bluetooth by going to the Applications menu:
1. Open the Settings menu, or return to the main Settings page.
2. Click on "Apps".
3. Click on the menu icon, then choose "Show system apps".
4. In the list of applications, click on Bluetooth.
5. Click on "Storage".
6. Click on "Clear cache".
Now, restart your Android device and try to re-pair your devices with it and use Bluetooth again.