Cancellation policy, and "Upgrade of line"= more costs

If I could give this company a minus 10 stars, I would have. They increase your contract with a notice, not giving you the opportunity to stay on the line you originally app**** for, when trying to cancel, they have a policy (PLEASE NOTE NOT THE SERVICE PROVIDER OPENSERVE) they have a policy of a CALENDAR month, not if you cancel the 6th until the 6th of the following month, NO, they charge you for the full following month. I WILL NEVER use them again.