Equipment Return and Plan Cancellation

I presently have a promotional plan for internet and mobile service set to terminate Oct. 14, 2026.  I went to a local Xfinity store on Sept. 24th to see what my options may be for the future, and was presented with a plan for both services for $65/month, for which I was agreeable.  I repeatedly and very specifically told the agent that I wanted this new plan to commence upon the termination of my current plan, and was assured that was how it would work.  I was also advised of a promotion for a computer tablet, which I also agreed to.  Very shortly thereafter I began receiving emails and text messages prompting me to initiate my plan, and from what I could gather on your website, the plan appeared to be initiated (it was very unclear to me).  I spoke to your customer service on Sept. 26th and explained the issue.  After some back and forth, the representative told me to go to my local store, return the equipment (I was also shipped a modem although I had not asked for one), cancel the new plan, and then I could start it later when my current plan terminated.  On Sept. 28th I went to my store to return the equipment and cancel the plan.  Explaining what had occurred, the store manager said that plans started immediately, and didn't appear to give much consideration when I told him that that was not what I was initially told (in fact I believe he may have been aware of this conversation with his agent, as he stood close by and repeatedly commented and interjected throughout the "signing up" process), and that the customer service rep advised to return the equipment and cancel .  They took the modem but said there would be a $40 restocking fee for the tablet.  When I pointed out that I wouldn't even have the tablet but for the misrepresentation of the agent, he advised I could call customer service and get a shipping label sent to me, and there would be no charge if I proceeded in that fashion.  I subsequently called customer service twice, each time explaining the situation, and each time I was told they would email me a shipping label for use at a FedEx store, but neither time did I receive a shipping label (the first time the customer service rep even called me back to see if I had received it).  With my second attempt, the service rep advised me to go back to the store and explain the situation and have them take the tablet back.  I did return to the store, but they refused to take the tablet (the female agent even accused me of being rude and disrespectful to her, which I do not believe I was at all; I think she was just frustrated because she could not address the sequence of events and initial misrepresentations that led to this entire fiasco, so this was her way of terminating our conversation and not having to deal with me any further).  So now I have no idea where things stand, I have a tablet that I cannot seem to be able to return (at one point I was told it had to be returned within 5 days from my date of receipt), customer service tells me to go to the store, and the store tells me to talk to customer service.  This frankly is not the way to do business, and is such a pittance for Comcast that it is ridiculous that it should be creating this ill-will.  No one I talk to seems to be either willing or able to help.  Can you resolve my dilemma?