I have an android lg flex with a large screen that I really like EXCEPT when I've turned on roaming even if I am actively using it a pop up happens quite frequently (from every 1 minute to every 5 or 10) even when roaming is checked on! This is driving me crazy!

Tmo knows nothing to fix this and from searches it seems that this is a known problem with this phone across many providers. So I'm looking for a replacement. I've been looking at galaxy A9 or A9 pro - but can't get it with a US warranty (not sold in the US and if I buy it in Thailand or Malaysia the warranty is only good in that country). If anyone knows and has used the phone it might be worth the gamble.

I need a 5.5 (minimum prefer 6 inch) screen, T mobile compatible, prefer ability to use sd card, really good optics/screen. Any help?