USB headphone not working for calls

[user12]

My phone is Samsung M31 . USB headphone works properly in every app except calls. It uses built in speaker . how can I solve this.

[xSteveuk]

Check your sound settings. ... Tap on Volume and similar settings to make sure your sound settings are turned on

[user12]

I have checked sound settings but couldn't find anything. It works fine in other apps but when in calls it switches to in call speaker.

[xSteveuk]

Does this help

Making a call

Connect the headset to a smartphone or mobile phone beforehand.

Operate your smartphone or mobile phone to make a call.

When you make a call, the dial tone is heard from the headset. ...

Press the + or - button to adjust the volume. ...

To end the call, press the button on the headset again

_____________

If they're still not working, your headphones are the problem.

If your headphones do work in another device but not in your smartphone, your phone's the problem.

Check your sound settings. ... Tap on Volume and similar settings to make sure your sound settings are turned on

[Pugs1957]

Do your headphones have a microphone?

[GBCyclist]

Same problem A32

[MissyEll]

Sane problem s22 bought 2 new headsets same issue