In ear headset does not work on the PC?

So a buddy is playing fortnite on the PC and he just has such a cheap in ear headset, at any rate he can't say anything so we're in the game chat and he can hear me too when I say something. What can that be

Does the HS have two jack plugs?

Maybe the headset has 4 ports on the 3.5mm jack,

one for ground,

one each for left and right

and one for the microphone,

The last many PCs do not support, you would need an adapter.

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