Can’t get any instruments to come through headset

I have been using zoom for years for music lessons, I always use the original sound for 

Musicians, in the last 6 months I cannot get my piano guitar or singing to come through my headsets. I even bought a new headset thinking it would help, nothing. I can get my instruments through my separate webcam but then it picks up all noises, I want to use the headset mic for instruments. I have tried it all, what do I do?