[Q] Unmodded HTC One M7 stuck in boot loop, unable to facory reset or enter recovery topic

Hi guys, I have a completely stock HTC one m7 that one day decided to get stuck in a boot loop. I've tried going into the bootloader(?) and doing a factory reset, as well as accessing the recovery menu with no success. It just goes back into the loop.
I've been told that flashing it(?) in fastboot might help? I honestly have very little idea what to do when it comes to this, so I was wondering if you guys would be able to help me, and explain in fairly simple terms what I need to do.

I've looked through similar threads but most of them seem to be problems relating to already modded phones. I hope you guys can help!

Thanks.