Harassment by DMC

I get a call from a DMC call centre agent just after 6 am today to ask me when I am going to pay my account. I informed her that she is not allowed to call me at this hour. She then goes on to argue with me and stated that she can call anyone from 6am. How ridiculous is that for DMC to harass people at that hour. I told her to do her job and check as the account was paid and settled a while ago and proof of payment was sent to the email address that was sent to me by DMC. I would suggest that DMC spend some time training their employees to do their job and check for proof of payment before calling and HARRASSING people. I am unwell and got woken up by a very rude DMC employee. Is that what they train their employees too do. I am disgusted as there is a thing called customer service and I can say that DMC does not practice that. I want a written apology from the manager of that rude employee. I will take this matter up with my attorneys if ii do not get a written apology as well as confirmation that proof of payment has been found. Further I want a letter stating that the account is settled and closed. This was promised to me when the arrangement was made but not delivered