Illegal Collectors keep calling

I just got a call from another one of these crazy illegal collectors. They keep telling me I owe on a payday loan I never had. I think I have gotten rid of them for a couple of months and then they start up again. This time they said they are ready to "press charges." My lawyer even faxed them a letter the last time they called advising them to contact him only. The letter was to Morgan & Associates. I called my lawyer again today but he is out of town. How can I get these guys to finally quit calling altogether??