PC Crashed, Flashing Lights and Won't Boot Back Up

Help! I was playing a game on my new PC build (I built it about a month ago) when it randomly crashed. No blue screen or overheating, it just suddenly shut off. When I try to turn it back on, the lights on the motherboard (an AsRock B450 Steel Legend) flicker and the power button does not work. I have no idea what caused this or how to fix it. I've waited almost an hour now and I am still having the same issue when I turn on the power supply. What should I do to fix this?

I tried clearing the CMOS, but it didn't seem to do anything. For whatever reason, my motherboard doesn't come with the cap you need to use the clear CMOS jumper... I had to take the battery out instead. I kept the battery out for 10 minutes and tested the voltage while I had it. After turning back on the PSU, I was met with the same result. One new thing I noticed is that when I hit the power button, all of the lights come on and the fans start spinning for about half a second, but then they turn back off, and the fans start blinking red. I have no idea what this means or how to fix it...

Time for a new PSU ..it died on you. Had same thing happen over the years on several different rigs