According to your screenshot, seems you were using Feature timeline and Epic Roadmap extension.
It’s caused by you are using a team based backlog/ Feature Timeline, not a project level.
How to select team-level iteration:
- You already created corresponding child iterations under the whole project.
- But you still need to select them in related teams.
Click the default team’s settings in you screenshot. You could also switch team in the drop down list:
3.select iteration you need for the team
4. Now you will be able to see child iteration in feature pipeline.
CLICK HERE to find out more related problems solutions.