Hathway — Internet subscription cancellation

As i was relocationg to a new location, i dint want hathway anymore and so i stoppped renewing. Later they kept on calling me for renewal and failing to which i have to submit router back. I agreed to send all the equiments back but no one showed up. Now i am getting a call that says i will be sued for this. Being a customer, its my decision choose or not to choose hathway. This is seriously affecting my mental health and taking lot of time answering to their cusomer executives. I need them to stop calling me and take their equipments back as soon as possible.