I see.. your trousers are made of empty.

Edit: those and weird sentences. If I must say it was not so easy what I thought buying a game.

Anyone getting this when trying to purchase? I add the game to my cart, go to checkout and it tells me ' your order is empty.' I really want to purchase Gangland, so I'd be so grateful if somebody could tell me how to fix this...?

Edit: Never mind, it seems I have to add to cart from main page, not the game card in order to make it work properly.

Several suggestions:

Try a new browser
Try re-logging
Try returning in half an hour or so.

Beyond that, the issue falls with GOG and you may consider sending a help-ticket.

You Are Empty confirmed!