How can I get correct information about drop/bury tech appointment?

My drop/bury was requested by inside techs and confirmed by Xfinity on March 27. My struggles are far too many to list here, but to say I'm unsatisfied is putting it mildly. I've tried in vain to get connected, but have been given false information along with a lack of communication despite all of my many efforts. I have a summarized list of my efforts and results (or lack thereof) that I want to share with someone and receive a response. I see instructions for direct messaging of complaints, but I see no icons that are described.