NED BANK CREDIT CARD, ALL OF A SUDDEN I OWE THEM

3 DAYS AGO I HAD 24K IN MY CREDIT CARD ACCOUNT, OVER MY LIMIT OF 23K. ALWAYS LIKE TO PAY ASAP INORDER NOT TO HAVE MUCH DEBTS. ALWAYS TOPUP ABOVE THE LIMIT. 3 DAYS LATER, I SEE THAT IM OWING OVER 8 K AND MY BALANCE IS 14K. IS THAT POSSIBLE. CAN THEY NOT SHOW ME WHAT I HAD IN MY ACCOUNT 3 DAYS BACK. IS IT A DELAY OR MISTAKENLY DEBITED MY TRANSFERS TO TOPUP OF 8 ON DIFFERENT DATES