Hello !
For the past week, as soon as I start a game, after 4-5 rounds my game starts running at around 60 FPS or even less, as shown here with the screen recording. It's very frustrating, especially since my PC has never had any problems running the game at 160 FPS until now. I feel like the FPS locks up in the game because when I go back to the menu, the FPS immediately goes back up.

Does anyone have a solution, please?

It's so annoying and unplayable, as you can see in the clip.