Need to escalate this

Got a new Xfinity internet account and every time I sign in, the one year free of one unlimited data plan promotion pop up.

I asked xfinity mobile online chat agent and I was told I'm eligible for this incentive if I port in a new line and make that line in unlimited data plan and the credit will be automatically applied. I did add a new phone line and add it to unlimited data plan. Several days later when I checked my account, I saw the billing is still regular price for that unlimited data plan. I then made a phone call to xfinity mobile customer service and the phone agent double confirmed with me that everything is properly setup and I just need to wait longer to have the credit show up. I believed that until the last day of my billing cycle, still nothing credit showed up. Then I made another phone call and this time the phone agent told me, because I added the line to big gig shared data plan first and then changed it to unlimited, the first billing cycle can't have the credit, but it will start from the second billing cycle and assured me again everything is properly applied. After my second billing cycle started, I then checked my account, still no credit at all. Then I made a phone call again. This time I was told the incentive was not applied yet and this is an xfinity internet incentive for mobile so I have to discuss with an internet agent. I was transferred to a xfinity internet agent, and after she reviewed my account, she told me I was not eligible for this incentive due to several reasons and she has nothing to do with previous xfinity mobile agents and can do nothing to recover my loss, given I have already used the data plan.

I feel I was played by xfinity like a fool. The whole thing cost me not just hours of my time with xfinity agents through online chat and phone calls, but also $25 activation fee to port in a new line, 2 * $40 for that unlimited plan. I don't think xfinity should let its agents do this kind of fraud like business behavior in order to generate more revenue. I trusted xfinity agent as the source of truth, but they just keep giving me misinformation to trick me into some wrong decision cost money to me. If xfinity concludes that I'm not eligible for the one year free unlimited data incentive, I think xfinity should at least reimburse the cost to me due to the misinformation provided by its agents again and again, and if I knew the truth from the very beginning, I would never make such decision which cost more money to myself.