Deck view columns not showing all of a sudden - what has been changed

[Ellie_F]

I have several apps set up the same way. the deck view uses columns that concatenate name and address or address and postcode. These were showing fine in the deck view but now have all disappeared.
It seems the issue is that they are selected in the deck view set up as the header and sub header but as they are not marked to show they are now not showing. sounds logical but they were set that way as I dont want these showing in the form view and it DID work and has been working for a long time but now something has changed. Please can someone tell me what ?