Account paid in full but still says i am owing..I AM ****ED

I have an account with THE FIX store which i paid in full on the 23/06/2020, i went to check my credit and i saw it says i am still owing so i went to the store(N1 CITY) and i was assisted by Zimkhitha who checked the account on their system and found that it shows i had made a short payment and i showed her a receipt that i paid in full and i got the amount at the store but she called the head office and they were completely useless....i was told by them i would get a call but nothing and i then went back to the store and they tried assisting but the customer care line they called couldnt help them..PLEASE SORT OUT MY ACCOUNT ASAP!