No Money THAT WAS OWING TO ME

i sold my house in 2015. Received account saying municipal owes me money R 447.74. I phoned to find out what i need to take in to their office. Took in the documents need. I was told in 6 weeks the money will be put in my bank. Phone on 22/01/2016 to get told they need bank statement n certify ID. Which i was not told about. Now I've got to go in AGAIN. WASTE OF PETROL n MY TIME. Now i want interest on the money owing to me. Account number ***, R 447.74 plus interest