I need to cancel my service from outside the country

I have an extended visa outside the USA and forgot to cancel my service. The chatbot keeps telling me to set up a callback but DOES NOT allow international numbers. I cannot visit a store because I am outside the country. I cannot do a callback because I am outside the country. Despite the chatbot saying I can be connected to an agent I cannot be because the chatbot is obtuse and unhelpful. I just want to cancel my service promptly. I would happily empower a representative to do this for me from within the USA but I don’t know if that’s possible because the chatbot is obtuse and unhelpful. I am incredibly frustrated, please help.