Angry and horrible service

I took mtn router online thr experience i.had with them for cancelation is a nightmare when i go to the store they dont want to assist me they told me i took it online and it is not a contract it is a month to month now they sent me the message telling me they have changed the cancelation date i will be billed why must i be billed for something i wont use the router is gone what am i paying for exactly