Weird. I got that message the other night when I restarted my AT&T branded S4. I clicked it and it didn't do anything and my phone registered LTE like nothing and has been fine ever since. I didn't think anything of it, though that is the first time I've seen it and I've been on the S4 for a month.
Originally Posted by beastliest
Castrol EDGE 0W-20 is my drug of choice.
Primary: iPhone 7 Plus, Galaxy Note 5, LG V20
Secondary: TracFones: iPhone 6s [AT&T] & iPhone 7 [Verizon]
Mobile Broadband: ZTE Z915 LTE hotspot (5GB for $10) + iPad Mini 4 w/ T-Mobile LTE