Hey, well, it's my first time, telling solution, so don't mind my broken English!
I have the same problem with BoAt Rockerz 450, i resolved it but temporary, like I have to do it again and again, I shut down my PC.
A) Well, go to sound by->
A1) Go to the 'Settings', then go to 'System', then select 'Sound'.
OR
A2) On taskbar, Right-Click Volume Icon, then select 'Open Sound Settings'.
B) Now, choose 'Headphones' on Output Device, and 'Headset' on Input Device.
Now, you can't hear anything, but your mic will be working.
C)After that, Go to 'Settings' Again(Refer A1 or A2)
C1) Click on 'Privacy', then Go to 'Microphone'(which is present in 'App permission' Section)
C2) Click on 'Change' Button(which is below 'Microphone access for this device is on')
C3) A small Pop-Up will appear above that button, on that Pop-Up, make it 'Off', and then make it 'On' again.
Now, your headphone's both things, are working(audio and microphone).
#But there is a problem, while you use microphone, you will stop listening audio, and when you stop using it, you can listen audio again, that is a or issue, but i don't have any other solution right now!#