Audio plays through mic

Hey so, im kinda confused, 2 days ago my headset was working perfectly fine I was chatting with my friends and then I went off, I left my pc on overnight and in the morning when I went to stream I had noticed my microphone was picking up all of my headphone output instead of my voice? I got into a call with my friends and they could just hear the music I was playing.

This is not a driver issue
Nor a virus

I have a GSP 305 Paladins Edition (Sennheiser)

I use Realtek Audio

I would appreciate if anyone can help me
or if I should just buy a new mic and headphones.