Connection to T-Mobile (US)

stlspartan

My daugter has a UMI Hammer S and I've just switched from a Zero to a Diamond.  We have the exact same carrier/contract, T-Mobile US,  Her Hammer S will connect at 3G and 4G while my new Diamond will only connect using Edge (E).  I don't see any difference in the listed bands/protocols so why will the diamond not connect on 3 or 4G?

MarcinP

Hi
Please check setting. If your network provider is third party please switch on roaming if you want using network data. Please go to settings - more - mobile networks - preferred network type - 4G
Then network operators - choose automatically .
When you are in network operators you can wait for search and check is 3G and 4G your network provider available on list.

stlspartan

Yes - checked all settings with t-mobile support.  I even factory reset the phone.  Interesting thing is that my daughter's sim will connect to 4g in my phone.  We are on the same plan. T-mobile is sending me to the local retail store for a new sim.  I didn't know the sim could be the cause of something like this. I've used it with several phones... Perhaps this has confused some back-end database at t-mobile.

MarcinP

stlspartan replied at 2016-12-26 11:59
Yes - checked all settings with t-mobile support.  I even factory reset the phone.  Interesting thin ...

Some sim cards are old shape chip cause incorrect Lte connection. Of course you could damage your sim card chip due to swapping between phones. This is common problem too.

MarcinP

Old sim cards could not support some network bands that why you can access to 4G on one phone but on other will not work as some bands are not compatible with some phones.