I've created a project using the Scrum template and don't change the default configuration. I have some issues in the backlog with the Epic->User Story->Task hierarchy. User Stories are displayed as swimlanes and I move a User Story to the board and It stays in the backlog with a nice blue badge with Sprint name. Just like the one in the picture
But then I move another User Story to the board and it just disappears from the backlog. At first glance, both User Stories look the same, so I can't figure out what it depends on. Could you give me a hand with that?
Thank you in advance.