[Edited] free watch and never agreed to a plan change

I called 611 for some help which went ok until the end of the call. He mentioned that since i've been a long time customer, i'm eligible for a free apple watch. he assured me that it was completely free with no charges. He never indicated that agreeing to having the watch shipped to me, that it would change my mobile plan.
Turns out that it wasn't free (monthly charges are showing on my bill) and it did change my plan. I was grandfathered into a 1gig of shared data plan for $12, which I was completely happy with and did not wish to change. So now everyone I've spoken with says I can't change back to my original plan. I never agreed to change my plan, I only agree to what I was told was a "free" watch. [Edited: "Inflammatory"] now I'm stuck on this new plan?