Account paid but not reflecting on system

i had a balance of R935.58 and on 02 Dec i paid R550.00 via EFT. On the 08 Dec i received an sms from foschini saying final reminder to pay R550.00. I ignored it because i knew that i have paid the money. I then went to the nearby store to enquire and i was told that the money does not reflect on their system. i gave them the proof of payment and they promised to fax it to headofffice. Half an hour later i received an sms that my account was temporarily suspended, why should they suspend my account instead of sorting out the payment issue.