We've been using a team-managed software project for about a month now, and everything was working just fine until suddenly some issues stopped showing on the board or the backlog, and they only showed in the Issues view.
Some of my observations based on the troubleshooting I did:
- The message "For issue MKT-123 to be visible, it must match your project and filters, and have a status that’s assigned to the board" shows when we created a new ticket.
- The Issue type doesn't seem to matter, as the problem affects them all equally.
- The status in which I create the issue doesn't matter.
- Having it assigned to someone doesn't matter.
- This message appears when I create the issue by using the Create button at the top of the page
- I don't get that message if I create the ticket from the "Add a child issue" from within an issue.
The screenshots below show an Epic we created that's In Progress but doesn't show on the board or the backlog, while it can be accessed fine from the Issues view.



There doesn't seem to be a consistent pattern on why some tickets show on the backlog/board and some don't.
I had an automation rule that moved newly created Issues from the backlog to the board, and thought that somehow this caused the problem, but we still have the problem even after disabling it.
I made sure that all the statuses are assigned to the right columns, and our workflow is quite simple as we allow moving from any status to another, and we don't have limits on tasks in each column.

I've checked lots of other questions in the community about this issue, but none seem to have the same exact problem, nothing that I could find anyway.
Any help would be really appreciated.