Why is my brand new fan not working?

Hey! My PS4 is an older one, it overheated and shut down for the first time last week. I noticed the fan wasn’t turning on so I replaced it and was able to play for a couple hours before my PS4 overheated again.

I checked it out and the brand new fan isn’t turning on at all anymore. So my PlayStation is doing it’s automatic overheat shut down when the fan is unplugged - except my fan isn’t unplugged and everything is put back together just fine.

p.s.

I’ve disassembled my PS4 multiple times and tried again just to make sure I’ve put everything back together properly.

Any help would be appreciated!