How do I get my email address removed from someone else's account?

Hello, 

I am not, nor have I ever been an ATT or DirecTV customer - indeed I am Canadian, so it isnt even an option for me. However, some months ago, someone signed up for DirecTV using my email address, and all information has come to me since - the schedule of their installation, their service changes, their bills, their notice of unpaid bills, their disconnection notice, and now Im getting all kinds of offers for bill discounts etc.  I wonder if your actual customer has no idea about any of your communications since you appear to not validate emails, nor is there any way for me to respond to the email or send back.   Really, I just want you to stop sending things to me about someone elses delinquent account, or account at all. 

On May 4, 2019 I was emailed that my service was due to be installed in 2 dates. That email was addressed to a "Richard Mercer" (I know no one of this name)  and had account number ***** flagged. There was no way for me to reply to or flag this email, so I ignored it. On Dec 6 2019, I received an email asking me to verify my email to enroll in online billing - I of course DID NOT validate this email, but apparently that doesnt matter and you allowed it to be considered validated anyways, and since then I have received bills, reminders, cancellations etc.

I cannot find a way to contact you about this at all besides this.  How can I stop AT&T from sending me someone elses personal information - the email address was never validated, and I just want to stop receiving this information.