Usually the problem occurs when water reaches the fans or the psu (power supply) or it overheats because of the safety lock that occurs when a lot of dust is in the fan, but the most common case is when the psu is faulty or isn’t plugged in properly. Try unplugging it then plugging it back in or try replacing the psu. If it still doesn’t work replace the fans that has a high chance of working. If you tried all this and it still didn’t work contact Microsoft. I had the same problem myself. Hope This Helps!