David Hi 👋 David,
I am using the bunq App on iPhone (🍏 iOS) and I managed to move the virtual card to any folder.
Are you sure you have the latest installed App?
If you use bunq on an Android 🤖 device I would not know but probably someone using that OS can confirm.
If that is a bug 🐞 and had not been reported then a support request with bunq (private chat where you can submit securely all type of info) is a good option.
Good luck 🍀
Have a great one 🌈