Unauthorized Billing After Verified Account Closure

I am writing to file a billing complaint against Comcast/Xfinity for unauthorized, continued charges on a closed account. I have recently relocated from the United States back to Germany , and I am entirely unable to reach Xfinity customer support, as my account has been locked and international calling queues are prohibitively expensive, and also arguably not very helpful most of the time.

Prior to my international relocation, I canceled my Xfinity Internet subscription. To ensure the cancellation was processed correctly and that no outstanding obligations remained, I went in person to a local Xfinity store. The representative closed my entire account, and I received a physical printed receipt explicitly confirming that my account was shut down and all services were canceled.

Previously, my prepaid mobile line had been transitioned to a "1-year free" promotional tier as compensation for prior service issues. Because this mobile line briefly remained active after the in-store cancellation, I reasonably assumed the prepaid promotional period would simply run its course. It now appears that Xfinity's system automatically executed a new billing cycle or applied hidden line fees tied to the mobile service because the internet service was canceled. This directly contradicts the in-person confirmation and the physical receipt of total account closure I was given.

Since my return to Germany, Xfinity has generated new invoices and attempted to charge my bank account for services I explicitly canceled in person. As these charges are unauthorized and violate the terms of our final settlement, I have instructed my bank to block the transactions under the Electronic Fund Transfer Act.

Therefore I hereby request an immediate cease of all billing attempts and wipe any newly generated, unauthorized charges or alleged debt from my closed account.
Otherwise I will be forced to escalate my complaint to the FCC.