I have a prepaid account with 10GB per month of 4G data. I purchased my S8 from Samsung with you as the carrier. The sim card came with the phone but I had to call the help desk to get it activated. I've had this phone for almost a year and the T-Mobile app has never worked! I can log in just fine but everything is grayed out. I have tried everything from wiping the cache partition, to doing a factory reset, with no resolution. Do I perhaps need to go into a T-Mobile store to get a sim card upgrade because nothing else has worked? Yes, I can access the mobile site just fine.
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