Tired of been called after arrangement was made

I have been receiving calls after calls from this attorney ,When I answer either Im disconnected or I cannot take the call and the call goes to voicemail,After confirming an arrangement with Standard bank and Wilhelmina from the attorneys I am still been harassed ,I will not pay R27.50 a call when the arrangement was already in place two days ago ,After receiving a breakdown of the billing I made it clear I do not want to be contacted ,Everything is in place yet I am been called for arrangements .Does this company not operate on 1 system are there no notes and if the payment is been made why are they wasting my money,<br> Treating customers fairly does include calling them and billing them for matters which have been sorted out,<br> I will not be liable for any additional costs relating to a company not updating their systems I have sent several emails to Wilhelmina and to date I have no response,