Am not owing the account

Good day, please help me, I had *****ulent activity taken please in October midnight, in the morning I went to Riverside Makro store to report the incident, they helped me to complete forms and I gave them all the documents they needed to send to ***** department, they contacted me and advise that transaction took place at Capetown and I stay in Randburg, they advised that they are still working on it, after 21 working days it was in November, I received the Sms saying that my account if fixed and I don't need to pay anything. To my surprise the account is owing and they hand me over. Debt collectors are calling me non stop. I reported with them no response.