We purchased several of these (ROG Phone 2) and they all have the same issue with T-Mobile, where they simply don't ring when people call unless/until the network is reset. Fastest way is to go to airplane mode and back, and then all the stale text messages start streaming in. But it isn't like it warns you when it needs to be reset. Instead, our guys know to call each other on WhatsApp (or similar) if the phone doesn't ring or urgent texts don't get answers. It is really frustrating and happens multiple times daily. Love the phone otherwise, but if it doesn't work as a phone, it is just another video game console.