Your phone will latch onto the most strongest connection type it thinks is the best.
So if a person just wants to use a wifi connection and not a network data connection then it's advised to turn off Mobile Data in your phones settings or via the pull down shade.
You can also set a preference settings in many apps on how they a, Send a notification and b, how they connect and update.
Daily Driver > Samsung Galaxy s²² Ultra 256Gb in Phantom Black.
The advice I offer is my own and does not represent Samsung’s position.
I'm here to help. " This is the way. "
