GSYNC Issues

Hey everyone, I need some help. I recently got an AOC Q27G3XMN monitor, and while it's great, something feels off. I set it up with G-Sync enabled in the NVIDIA Control Panel (fullscreen mode), but when I tested it in a game, the performance seems weird.

Whenever my FPS drops to 60-70, it feels like a stuttery slideshow—definitely not how G-Sync is supposed to work, right? Even at 100 FPS, it doesn't feel smooth, which is really concerning. Am I missing something in the setup, or is there an issue? Any advice would be greatly appreciated because this is driving me crazy.

Thanks in advance!