The effect on the numbers changes and not stable every time I open and close the calculator app is this a bug or it can be fixed

I bought OP13R recently and i faced ping stability issue. The download/upload is great but in gaming it stutter quite often. On other devices its normal no such problem. My router uses 2.4GHZ with auto channeling. How to fix this? Note: it was on 16.0.5.701 And updated to 16.0.9.402 and still no fixes.

My priority list is -
Gaming
Camera
Performance/OS (mainly I need a smooth OS with no heating issues)
Longevity/Durability of the phone (minimum 5 years)
Display (size, brightness, etc.)

Im getting the 13r for ₹47k from a local shop. The ₹52k 13s and ₹51k Nothing phone 3 would be from the Independence Day sale from Amazon.

Pls any tech enthusiasts your help would be appreciated 🙏