Sales reps. Are never responsible if it's not a sale

My contract with my employer ended August 2017, I called for assistance in regards to my account and I was advised to send my documents to my nearest cell c branch. I was assisted at Protea Glen Mall Soweto by a guy named Mpumelelo in September. I was told the documents have been forwarded to head office, till date I pay for debit order penalty of R61 for an inconvenience and incompetence of an agent. Today I visited the store to lay my complaint and he claims I never provided him with the information to be a cash client. I was told head office will deal with the situation and whenever I call customer care my issue is excellated and not resolved. Now I am at the branch and all I get it bad attitude from the agent that took my documents. I filed a complaint with the store manager and the guy has been giving me attitude and talking back. I am not happy with the service