Refuse to pay back credit

Its been one year and two months now since my mother has passed away.....doe to her passing i had her telkom line canceled.... that took three attempts to do.....then i still had to pay the account for a short while....going into a credit balance i received an account that said unclaimed refund....after months with dealing with the lady at the credit refund department,she rep**** with a email saying sorry we cant refund you your credit amount of R34.09 as your mother use to get a debate discount on her connection.....how is this possible??????