I recently created a new issue type and associated workflow. It was working fine and I created a couple of tickets using it. This morning it has disappeared from my backlog.
To be clear:

Tickets still appear as linked under tickets of other types
But when I go to filter by 'type' in my backlog or when I search for the ticket code or scroll to where the previously appeared in my backlog, there is no sign of them.

I don't have any filters applied, so can anyone help me understand where my ticket/ types have gone?