Your only solution is buying a good thermal paste and isopropyl alcohol to wipe the old thermal paste. During that you're gonna have the CPU heatsink and fan out of the case, so you might considering giving it a clean aswell.
If you're lazy you might consider the option below
WARNING: This will turn your room into an airport (Real talk, after u play a game for 15 minutes you will see)
Enter your BIOS and disable Cool & Quiet
Boot to Windows, install SpeedFan (there's tutorials on how to configure)
Set everything to 100% and make a schedule so it runs each time Windows starts (there's tutorials on yt)
Next: Play a game for 15 minutes and check your temps. Your RPM should go up to around 6.8k RPM unless you're using an aftermarket cooler. This method only works on the stock AMD cooler