Disappointing conduct from Checkers Oudtshoorn

Very disappointing experience. Bought groceries at Checkers Oudtshoorn worth R980 last month, my card declined at the till point. So I left the trolley there. Luckily, the lady who packed my groceries knows where I live. She informed me my groceries did indeed go through, I'm sure it was a glitch on their side. I then went to state what had happened, the man who assisted me said I should bring a statement that substantiates that it indeed went off on my account. Brought my statement and was assured that they will be in contact. Till this day, I have heard nothing from them regarding refunding me. Whenever I do call 044 , the manager is always busy or the call gets dropped. Going in person proves futile too.