I can’t help you much, but googled it a bit and someone had an issue with a Unity game in 2016 with their PS3 controller not registering. But it did tell me that the game was made with the input system “Rewired”.
Rewired - Advanced Input for Unity page-139
First link has some info, not enough that I could tell you how to fix it. Second link is the Rewired forum thread, I’d suggest searching that thread a bit and see if someone else had done similarly before. Also, would be helpful to know which game in case someone else also owns it and it willing to screw around with it for a while.