Record the phone call and file a harassment complaint. That is the best thing you can do right now if you really want to take this to the law. I would try and visit them or talk with a manger.
You can do some in depth research on the subject by searching the web for a topic close to your case: harassing collection agencies
Here's a decent example
http://www.lawmo.org/law_fdc.htm
Instead of yelling at them, start yelling at your brother and tell him to pay his damn debts. That will make the calls stop instantly.
How to get payday loans to quit calling me?
T.R.Y
T.H.I.S.
S.I.T.E
W.H.E.R.E
Y.O.U
C.A.N
F.I.N.D
T.H.E
B.E.S.T
S.O.L.U.T.I.O.N
F.O.R
Y.O.U
So evidently my brother took out a loan with payday loans and put me down as a reference without telling me. Now they keep calling me for him. I told them that I didn't authorize my name and number to be given out and to take me off their list and quit calling me. She said rudely if you promise to tell him to call is I'll take your name off. I said whatever and hung up. Now its a few months later and their calling me again. I just don't answer but want it to stop!