My phone seems to go into some kind of “sleep mode”. It’s a galaxy s7 edge, an international phone that I bought elsewhere. I didn’t have this problem right away, it started earlier this year. Occasionally, my texts don’t go through and I have to send them twice. Usually, when that happens, and the second text goes through, I get a bunch of delayed messages. In that time frame, phone calls would also go straight to VM. I spoke to t mobile reps and they send me a signal booster but that didn’t solve the problem. I depend on this phone for work… I downloaded the LTE discovery app. TMO BYOD is no longer avail in the app store. I’m located in LA. Any suggestions? Thanks, S.