Athlone park Checkers gift card *****

i have a bad experience with checkers at Athlone park , i was loading my gift card from March 2024 only find that the amount that is in my card is R500 and i launched a complain from the store they requested the statement from the head office and they get back to me and said the card was redeemed twice, i am sitting with the card knowing that i have a money only discover only have lousy R500 and i discussed with them and they are saying there is nothing that they can do , cause they changed the system this year and it wiped everything and i asked the solution to this matter and they say nothing, my plea to you is to assist, the manager name that i spoke to is Vani who was on duty. i am so dissappointed with the Athlone park checkers and i wont buy from there anymore, just to advice people dont trust that store ever ever again.