Disconnecting from WiFi at night?

Hello, I'm experiencing a problem with my iPhone 12. The phone keeps disconnecting from WiFi only at night for several minutes. The bar is still there but the phone isn't connected to the internet. Afterwards there will be a log in analytics called "WiFiFWTrap" (WiFi firmware trap). I'm wondering what causes it. I've already restarted the phone a few times and I also restarted my router, it still happens. The first time it happened was about 5 days after updating to iOS 16.0.2. Now I installed iOS 16.0.3 and it still happens.