Default I need Internet!!!!

Not too long ago i upgraded my phone to zen 4.3 ([ROM][4.3][Dec-2013] AT&T I317-UCUBMK6/MJ4 *Stock* Rooted Odex/De-Odex/Odin) everything worked fine including root as well as wifi, but i had just one annoying problem i was NOT able to use my mobile data. i have been looking for various ways CHANGED Apns, modems, REsort back to other stock rom and back to 4.3 again but to no avail. Now i'm runing ezkat v2.0 everything is great but i'm still facing the problem of no mobile data connection to my phone even though i have a straight talk line on it. I get text message but can't use the group features, can't do anything without wifi T.T Pls help a dying phone come back to life.......Version I317UCUCNE5