Purchases go off account some weeks later!

I've been banking with Nedbank for over a year now but have recently noticed that they do not take the money off my account immediately after a purchase. The bad part is, neither is the money \reserved\" for the purchase. For example, I recently had a Fochini purchase go off ONE WHOLE MONTH after the payment/purchase! <br> <br> This is ridiculous. I've only experienced this with Nedbank. Hiw can you pay for something and it be taken off your account weeks later when you dont expect it/there's no funds available. You guys need to sort this out."