Bluetooth headset connected but no sound

I installed ubuntu mate just yesterday and there seems to be a problem with Bluetooth. The device's window of Bluetooth is showing my headset and it's connecting without any problems. But there is no sound coming. I have tried changing the audio profile between A2DP sink and HFP but whenever I change the audio profile, the headset disconnects and connects again with the A2DP profile. I don't know what to do. I am new to Linux and don't know much about coding.