I've reached out to numerous marketo employees and have not been contacted back, can someone please reach out to me at firstname.lastname@example.org with instructions on how to end this service.
If you have questions about your subscription email email@example.com, they can at least direct you to the appropriate person.
Your business has purchased either a one year or multi year subscription. At the end of your contract term your Customer Success Manager will reach out about renewal, and at that stage you can ask not to renew. If you know who your CSM is, they are the best person to reach out to and discuss options.