I am also facing the same issue since I have moved to Samsung Galaxy M31. With my old phone, everything was working fine, but with Samsung M31, slow internet is a big problem.
The same here.
last weeks something crazy with network: it turns very-very often into H+, and until restart (or enable/-disable airplane mode) it becames in H+...
Dear Samsung Team, please help, or you'll lost customers!!!
Iam using Airtel sim in mobile..this is the fastest 4G network in my area..after starts to use this mobile, iam facing network problem very badly while others getting good network speed in the same network