Unresolved escalation with xfinity mobile customer service

How do I send a Direct Message to an xfinity Mobile Escalation Manager to resolve an ongoing issue with xfinity mobile billing? Five weeks ago, I was told that I would receive one free unlimited Xfinity mobile line for two years. So I signed up for xfinity Mobile Select. However, when I called xfinity mobile on May 2 and May 15 to discuss my xfinity mobile billing issue, I was told by a different Xfinity agent that I was "not eligible" for the one free unlimited Xfinity mobile line. I would like to send a Direct Message to an Escalation Manager to resolve this issue.