Keyboard Command key not working

Hi everyone,

I recently (about a month ago) bought a new v100 gaming keyboard. I hooked it up to my Macbook Pro and setup my keyboard and at the start every key was fine. Then suddenly today, my keyboards command button (which is the windows button) stopped working even though it was fully functional before. I first encountered this issue, when I tried to switch apps and failed to do so. I then tested out more functions requiring the command key (cmd+t, cmd+c) but none of them worked either.

Can anyone help me fix this?

Thanks.