Hi Fiel-kun, I'm Diana.
This is a duplicate thread of:
viewtopic.php?f=34&t=1002I don't think there is a bug. I will check around anyways, since multiple people reported having an issue with the shops. If it persists I will add a confirm yes/no dialogue like in the pumpkin event shop before it tries to process your order.
A few questions:
Did this happen to you using the cart/bulk purchase or the individual buy buttons on the items?
Are you on mobile (android or ios), or on a desktop (what browser)?
Currently there is no way to sell items, but you can trade other users for other items/feathers.