misleading "live chat" offer and impossible to get resolution

I am a 24 yr subscriber.  I received an offer from ATT and a competing offer from Xfinity. The xFinity offer included (1) $100 visa card (2) "free" xfinity mobile phone to replace my land line subcription and free wireless phone service (3) $40 reduction on my monthly bill from current $234 or so (4) option to retain these benefits even if I cancel the wireless phone after i receive it (i explained that my family no longer uses or needs the land line).

Its 5 weeks later, I have received and activated the xfiinity mobile phone it now appears on my upcoming bill as a $25 charge.   My xFinity wifi/cable/landline bill for next month is unchanged, even though my landline is dead.  I have received no written notification (by email etc) of the authorized changes in my plan, no $100 gift card. 

It is impossible to get customer service help.  Three calls in 3 days, each beginning with the obligatory bot chat, then live chat, then live call with overseas agent, then live call overseas supervisor. then one supervisor reaches out to another supervisor, then either I just run out of time or line goes dead.  NO ONE CALLS ME BACK (xfinity is a phone/communication company).  No one has authority to receive an email containing the transcript of my chat from 3/16 where these offers were made explicitly.  NO one has the authority to look up in xfinity resources and read the chat.  Spoken to reps in South Africa, and USA and other countries I didn't think to ask. 

This is a terrible scam.  I've spent over 5 hours on this already this week.  Shameful.  I've paid hundreds of bills from Comcast on time.   Xfinity team: Please read and help, potential xfinity customers: beware.  XFinity team members: see my chat id - [Edited: Personal Information]

EC