iPhone doesn’t load apps without wifi.

Apps that require wifi to work on my phone, don’t work without it. If I’m in an area with the best service but no wifi, my apps won’t work. I have unlimited data, have turned my phone on and off, updated it, even took the SIM card out and put it back in. I can still call and message people without a problem, and use safari thankfully. I’ve had this issue for at least four months and have even gone to my service provider, tMobile, them telling me it was a bug with apple. Any help is appreciated, please just don’t tell me to try doing the same things I already have.