Cancel my payment plan!

I have had endless trouble trying to cancel my Creative Mail payment plan due to them having no customer service to contact. I haven’t been able to use the services for over a year and I have lost out on months worth of payments, I feel like I’ve been scammed due to the lack of customer service I’m rightly entitled to.
Please do something about getting my payment plan with Creative Mail cancelled as it is stress I do not need. I wait to hear from you.