Edgars account active, even if i closed it since 2013

I have closed my account believe in September 2013. Note, when i closed it the service provider only said that the account was now closed. Did not get an mail or sms, anything. Its now November 2018, 5 years later. Received an phone call that i still have an outstanding balance of R187.00. I went to Edgars and asked why i still have an account open and stated that has not been closed. Why after 5 years need to follow-up on moneys i dont owe to you.