My ps4 shuts down by itself beeps 3 times but no red light or over heating warnings

Whenever I start a big game like FIFA or Warzone The fan kicks into high gear and. PS4 beeps three times and shut down By itself. No red light or overheating warning pops up. Recently I open my PS4 to clean it and I lost the thermal pad And by mistake I erased a little bit of thermal paste from the CPU chip. so my question is that is it overheating problem? Any help would be fine guys thank you.And yeah I can Play small games(by size) and YouTube videos

Also I have a PS4 slim