How to show the Issue hierarchy on the roadmap?

On the roadmap, you can set up a hierarchy with 3 different levels - Epic, Standard Issue, or Subtask. However, it's important to mention that,

For any issues types or child issues to appear in Swanly's roadmap, the start and end date must be assigned to the issues. There are three ways to add the start and end date. The first option is through Jira, and the others are through Swanly. 

To schedule the issues in Swanly,

1- Click the "+ add issue" button and see if the child issues are showing up to be scheduled.

2- If so, you can drag and drop them to the roadmap, or click one by one and add the start and end date. 

Also, it is necessary to enable the Hierarchy Epic level in Swanly. (see the screenshot below).

Open

To know more about this, please see: Issue hierarchy, and Schedule Issue.