It really bugs me to get a phone call from a CA.....AT WORK! I tried to explain to the man that I do not owe anybody anything....(except for my daughter. I still owe her for last weeks' allowance) He tried to persist that I needed to talk with him to get this "account" squared away. Well I kindly told him not to call me at work anymore and I hung up. I hope the "click" didn't break his eardrum. I feel like screaming....UUUGGGGGGGGGGGGGGGGGGHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Now I know how good Charlie Brown used to feel after this moment. =oD
Just because you tell them on the phone not to call you, doesn't mean that they won't call again. If they do call again, get the name of their agency, address, phone number, an account number to reference, and the reps name. Then fire off a C&D letter ASAP! That should put an end to that. If not, then they are in violation!
There's another way to handle this, but you may not want to. You can always put a supervisor on who will tell the jerk that you are not permitted to take personal phone calls at work and that these calls put your job in jeopardy. Then you can follow up with a C&D letter that memorializes the supervisor's words and also tells the CA that if they continue the calls to your workplace and you lose your job, you will sue for harrassment and for replacement of lost wages.