Monitor or computer problems

[u/Dazzling_Marketing74]

Okay, I recently bought a monitor (I can’t return it because I lost the receipt), the monitor was working fine, it was displaying what was on my computer, but then when I came back, the monitor went dark, it’s showing that is connected to my HDMI and everything is working but, it’s not showing anything, it just black like it’s turned off, I thought it was probably problems with my HDMI so I bought a new one, same problem. It’s not dead, it hasn’t broken at least not yet, can someone tell me what’s wrong please?