Cancel service after moving overseas

I’ve permanently moved from the US to the UK and need all Xfinity services at my former address disconnected as soon as possible. I can’t receive a US callback, and the Xfinity Assistant and out-of-footprint moving flow have not provided a way to cancel online. I also still have the rented gateway in the UK and cannot return it through a US UPS Store; I understand an unreturned-equipment charge may apply if no international return option is available. Please have the Digital Care team invite me to a direct message so I can provide the account name and service address privately and complete the cancellation.