I am building a plan from an existing Scrum board. On the Scrum board I have an Epic with issues - two complete, two in progress. In the "Confirm what's in Scope" step of building a new plan, I see the Epic, but not it's child issues. All the child issues have a Fix Version and the fix version is selected in the previous step of 'select the releases'. Why are the child issues missing? How do I bring those over to Advanced roadmap?
This page is an excellent resource for helping you to track down why issues might be missing from your plan: https://confluence.atlassian.com/advancedroadmapscloud/missing-issues-1026042894.html
Other things to check might be simple things like your hierarchy range and filters that you have applied.
Out of interest, are you using Server or Cloud?