Read This If You Own An Alcatel Pop 4 Plus Phone

I was having seemingly random problems with my phone spontaneously rebooting and even getting into boot loops.

Then it seemed to go away, but I didn't realize why, at first.

Other forums mentioned that the phone seems to have problems with T-Mobile SIMs if the second SIM slot is left empty.

When I was having my trouble it happened to be when I was using a T-Mobile SIM. I had subsequently switched to a FreedomPop LTE SIM and never had another problem. It never occurred to me that the T-Mobile SIM could have been the problem.

A friend of mine recently unboxed a Pop 4 Plus that was purchased last Black Friday and had the same problem with her T-Mobile SIM. I gave her a spare FreedomPop Global SIM I had laying around and she installed it in slot 2-- and she hasn't had any problems, since. T-Mobile works great. The Global SIM works great. And no random reboots.

The phone seems to be fine with one SIM as long as it's not T-Mobile.

If you use a T-Mobile SIM then you need to put another SIM in the second slot.

It sounds crazy and I initially ignored what I'd read, but it does seem to be the case.

"It sounds crazy and I initially ignored what I'd read, but it does seem to be the case." This is somewhat similar to the sound problem people were having with Moto E(2nd gen., I believe) phones, where the fix was to cover the background noise eliminator microphone on the on the backside of the phone with a small piece of tape. A case of whatever works, works.

Very curious experience! We have a Pop4 Plus in the family, but have never used a T-Mobile SIM in it. I'm adding this to my "device notes" file for future possibilities.