Cart still full after customer pays for order...bug?

Is there a reason why after someone orders that their cart never empties out after they have paid for their items?

Someone order an item and then paid with paypal. But when they log back in to their account, it still shows what they order in the cart. Should this not be blank now?

I had them log in on different browsers, thinking maybe it was a browser issue. Not browser issue, because they used a browser they never used to order and as soon as they logged in the cart showed their last order (that was already paid for).

Maybe I am missing some setting. Does anyone know why this happens? Is it a bug?

Thanks,

Kim

it does not happen to me and has never happened. you must have caused this your self with with some extension you installed.

or some bad configuration. i'm not going to wast me time checking this.

Here.

thank you