S2218H, Line-in port not functioning with microphone

Hello, I am trying to connect my microphone to my Dell S2218H monitors Line-in Port. However, the microphone does not work this way and I cannot find anything in my sound control panel that gives out any sound from my mic either. The line-out port works perfectly as I am using my headphones to listen through that port however the line-in port has no response whatsoever. I have checked by plugging the microphone to the back of my pc and it works completely fine but my pc setup is far away from my table and I wish to use the microphone from my monitor itself. I would appreciate some assistance, thank you.