Since I have Echo, Dots and Taps going on nowadays, I just ask Siri to turn off Bluetooth on phone or tablet if I am finished using it. Easy. When I want to connect BT again to an Alexa device, I tell the device to turn on Bluetooth, then turn on BT of phone again, auto-connect, and I am in business again. Easy, too. Have no BT problems, (except when I turn on wrong Alexa device by mistake!).