Block national roaming?

Is it possible to block national roaming on the H818P? Sim card 1 has an annoying tendency to not go back to the primary carrier once back in an area where roaming isn't necessary. This wasn't an issue when I had an xperia D6633 so my guess is that it's the G4 that causes it.

I would rather miss calls and texts than have to manually set it back to my provider every time to get the 3G/4G worrying again.