If I upgrade my basic flip phone to the iPhone and decide not to use it and use my basic phone instead will I still be charged for data?

I upgraded my Next Every Year and Next 30 phones to iPhone X's.  I ordered the phone and did the Next upgrade through the Apple App.  The phones were shipped directly from China and inside the box was nothing but the Apple iPhone Box wrapped in plastic.  There were no instructions, nor return label.

Dealing with AT&T saying I didn’t return my old phone after I upgraded. I returned the phone on December 7th. Newgistics recieved the package on December 11th and AT&T recieved the Phone back on December 13th 2017. So tracking number shows delivered by Newgistics to AT&T nearly a month ago.When the

I went into a att store to have my number ported over from a different carrier and also upgrade my line for the bo go offer. I went instore because I was unsure of the process of porting over a number. The in store rep told me that I needed to purchase a new phone first and then I would be able to p

When I eligible for an upgrade?