Excessive phone calls before 7am

I receive approximately 3-5 calls a day from MBD from Monday to Saturday starting from before 7am. I have an account with gets paid monthtly via debit order without fail. I have called in to ask that this calls be stopped, some of these consultants are extremely rude. I get charged for every call MBD makes. It is ridiculous and unacceptable, if i missed a payment then by all means call me but I haven't.