cellular data doesnt work on ios 14.5 anymore!

I am still without Cell Data. I have been to Tech Support 3 times and had 2 tickets written, 53732084 and 35387896. One Tech person never called me back one did 3 hours after the scheduled time and one is 4 and a half hours late… One Tech told me it was a phone problem, call Apple. Apple tested the phone, hardware is good. Reset like factory and no change. Service center wiped all software from the phone and re-flashed it, no change.  Currently running 14.6. A helpful rep at my local store worked the problem for 2.5 hours and thinks the problem is with permissions to access Data but can not get any help from techs higher up. I am in a position where T Mobile and Apple are pointing fingers at each other. I personally think the guy a the store is correct about permissions. I am headed back to the store tomorrow and if I can't get resolution I am thinking of moving to Visible. This thread should not be marked as solved, it is NOT! Does anyone know how to get to higher level tech/customer support? T Mobile are you listening?????