$60 for new tablet, home internet and new tablet line - wrong billing

Hi,

Last month, I was offered a deal by an agent when were talking via live chat. The offer was if I purchase a new tablet and new tablet line, my total bill will be $60, lower than my previous bill. Even though I did not need a new tablet, I accepted the offer. 

I was told that I will receive $40 credit for 24 months to my home internet bill after I activate my new tablet line. However I still do not see the credit on my home internet bill yet and I am being charged higher than what I was communicated. 

Luckily I had downloaded all live online conversations at the end of the conversation, so I have proof.

I saw tons of similar victims on the form on the same promotion. This is like a scam!

Hope Xfinity support team can help me on this and address this disappointing customer experience.