Christmas Door 3

Is anyone else having a problem with Door 3 not opening? ?
I am not getting the task and at this rate i will miss out on a Ruby

worked fine for me.

Is there a bug - don't appear to be able to build ruby store.
1: It's asking for gold on a level that does not require
1: it's adding it to a building on a fort which is fully completed and requiring gold to be used