How to stop and report collection agency harrassment?

My daughter wrote a check that bounced. She did not know it bounced because she went to navy boot camp and had closed her account not realizing that this check was still outstanding. Her mail was still coming to our house. Several months later she received a notice of a certified letter. I signed for the letter and opened it. It was a demand for the amount of the check plus fees. She paid that. A while later there came another demand from this same company demanding $2.98 for mailing fees. She paid that. Then several months later they sent back that check stating that she now owes $100.00. I called them to tell them that there was no way that they were going to get another $100. and to stop sending these notices. The man I talked to was extremely rude and threatened to go to her chain of command and turn her in, he threatened to ruin her credit etc., etc. I told him to go ahead because we won’t pay him any more money. The then called my house and threatened me again with court and said he would go to the neighbors to find out where my daughter was. Well, I thought that was an empty threat but apparently he did call my neighbors house! My neighbor just told me that h e called them asking questions about me and about my daughter. I think he has gone way too far. What can I do to punish this action and to stop his harrassment?