Unacceptable delay between using cards and deducti

I have private client status with FNB and my complaint is poor service wrt my debit and credit cards. I find a delay of up to a week from swiping my card at a various shops or petrol stations, to the transaction actually going through and the money being deducted from my account. If you require a list of vendors where I regularly experience this, I can give it to you.