LG Stylo 2 Plus lost data connection

[AC Question]

I bought two of these phones about a week ago - one for me, another for my sister.

Both phones working fine until mine lost the data connection. No internet or email.
I know it's the phone and not the service (T-Mobile) because with both phones side-by-side my sister's works ok, but no data for mine.

I checked the phone's settings: Mobile Data = ON, Limit Mobile Data Usage = OFF.
All my settings are the same as my sister's phone. I have an unlimited data plan.
Per T-Mobile's troubleshooting guide I removed the battery & SIM card and reinstalled. Still no help.

I'm getting the feeling it's a hardware problem with my phone. Before I call T-Mobile does anyone have an idea? Thanks.

 

[belodion]

Have you tried your sister's SIM in your phone, or your SIM in hers?

 

[PerfectlyFrank]

Maybe a bad SIM card? I'll swap cards and see what happens. Thanks, belodion