Question cs at 299fps usually now dropped to constant 30

[helpimbadwithcomputers]

computer specs:
-i5-9400f
-asrock b360m pro4
-16gb ram
-rtx 2060

It started out running at constant 299fps in csgo then everytime I start up my computer the fps slowly drop and in the end my fps was at a constant 60. Aft that I decided to reformat my computer too see if that helped and it did. But the next day, my fps in csgo decided top drop back to 60 and stay there
Guys please help me ive tried all the things I could. I have ran out of ideas and I still have no clue what the issue is with my pc

 

[Lutfij]

When posting a thread of troubleshooting nature, it's customary to include your full system's specs. List them like so:
CPU:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:

Meaning we're going to need the PSU, chassis and OS. Include the version for your OS if you're on Windows 10.

Might want to see if uninstalling your GPU drivers using DDU and reinstalling the drivers with the latest off of Nvidia's support site changes your experience.