Harassment By Bradlows company that I don’t owe a cent according to my knowledge and records.

I called Bradlows asking for a settlement quote and they sent me the lady who was assisting me asked when am i going to make a payment?I then responded to say immediately when u drop the call,my banker asked for them to email it immediately as we were going to make a payment.We made a payment as per letter emailed to us by them.At this moment I am harassed by their consultants everyday from morning till night asking for their money. What’s frustrating me is that their consultants have different amounts,one minute I owe R60,00 the next minute I owe R90,00 then another amount of R600,00 can I be assisted with these ******,they even say I am dropping their calls whereas I asked for one of them to give their superior the phone.The guy said I must wait after couple of minutes then he dropped the call.After few seconds I get a call from the lady she was now talking to me as if I am a lunatic accusing me of dropping the call I tried explaining to her what happened but instead she was forcing me to agree that I dropped the call.Can I be assisted because this is pure harassment.How do u give settlement let the still owe?I don’t understand can I be assisted with this case urgently