How can I enable different start/due dates to Issues in Roadmaps so they appear sequential

[Alex]

I have 3 sequential issues in my Sprint. All the Story Dates in Roadmap are defaulted to the Sprint Start/End Dates.  They all appear to start and end in the same Sprint with no differentiation. How can I enable different dates so each Issue appears to have a Start Date after its predecessor finishes all in the same Sprint?  I don't need to Link Issues (Start After or Relates To)

*********Sprint*********,*********Sprint*********,*********Sprint*********

************************* Epic************************

        Story                         Story

                 Story                          Story

                          Story                          Story