After using attempting to livestream using OBS (Open Broadcaster Software) I tried ending the stream by clicking "stop streaming" but I noticed it wasn't working, I thought maybe my computer was just playing up (I hoped not it's 2 days old) so I just pressed Alt-F4 to close OBS.

After not getting a response from any left clicks I shut down my computer, thinking OBS was still running in the background and it was somehow interfering. When I logged back in to my PC I then realised that infact I was just not able to left click. After trying to uninstall some programs to see if this would fix the issue I got out my spare mouse, and that one worked perfectly. I tried sfc / scannow, uninstalled all my recently installed programs, un-installed my anti-virus and Razer Synapse 2.0. I read somewhere that conflicting software may be causing a problem so in the end I decided to restore Windows, and still my left click would not work. However when I re-bound left click to my 1 button on the mouse, it worked fine.

After all that I finally considered that my mouse might actually be broken. So I plugged it into a laptop to see if the left click was working and it wasn't. The timing seemed all too perfect for the reason to simply be that my mouse button is no longer working, and I read through multiple troubleshooting articles and forum posts from people with similar problems but none of the solutions provided worked.