Cancellation request nr needed two years later?

Went into the Centurion Branch in 2021, to cancel an account that we would be using anymore, sat at a desc,cancellithe account with my wife as we were both signatories, system showed cancelled, asked for proof of cancellation, she said it was cancelled, two years later I get a letter of demand stating that if I don't pay an outstanding balance of the account I'll be blacklisted as this account was handed over to lawyers to collect the outstanding R250. Now I need to go into the bank again as there is no record of the cancellation and I needed to get a cancellation request number. Why was I not informed that I would need the cancellation number two years from the point of actually sitting in the bank and cancelling my account?