Differing information among the agents

For months i have been working on changing my payment date and for months i have been strung along.  I have always had to contact you and have it changed or moved because i am paid once a month.  I did that and because i intend to cancel services in a month the agent advised me that the right thing to do is set a cancellation request and leave it open to avoid interruption.  I thought it was incorrect and i was clear that i did not get paid until the 30th and because the post time and debit times are different i said the 31st.  Low and behold this morning my account was hit.  I reached out because i knew he gave me the wrong information and then i hear nothing can be done its being disconnected tomorrow for todays declined payment.  I had a 12 month arrangement option but got an error at the end and i find out it errored because of the agent doing the wrong thing.  this is why i was cancelling the service!