Cannot make a phone call
Cannot make a phone call.
Some smartphones and phone apps do not support hands-free calls.
Cannot hear the caller’s voice.
Press the call button to switch to the call if it comes while you are listening to music on the headphones. link
Check that the power of the Bluetooth device is on and the Bluetooth function is enabled.
Select HSP or HFP as the Bluetooth connection profile on the transmitting Bluetooth device. For details, see the Owner’s Manual of the Bluetooth device.
Check that the Bluetooth device is set to handle calls through the headphones. For details, see the Owner’s Manual of the Bluetooth device.
Increase the incoming call volume. link