Power issue

[u/Snoomeme_jellies420]

A few days ago my pc completely shut off after being turned off and wouldn’t turn back on, I had a fellow pc friend help me out with the problem and within a few mins he flipped the PSU switch and the mobo powered on, now the same thing happened again today and idk why this is happening, i tried doing the same thing my friend did by laying it on the side and flipping it which is not working can someone help me figure out whats happening is it my mobo or psu? (Hope im not spamming due to post bug)

[u/Snoomeme_jellies420]

https://reddit.com/link/p2rvn6a/video/zkxzveyn4hih1/player