Hi, we have an error appearing when trying to view an Offer Space.

And we also get this error XTK-170036

and then we get this error

I have tried to delete the Field that has disappeared from the Offer Space, but the Delete icon is grayed out.

There does appear to be problem with this same field working on our other Offer Spaces. This Offer Space is now rendering an error on the Preview for each of the Offers in Design and Live.
How do I fix this?