Make sure the sprint which has the stories is set as active and running. Also check the project management setting is set correctly for the planning tool you are using. This is found under general settings.
You can do that within the devolper portal in the Stories or Epics tab.
In Studio Pro check the source here:
This can be Epics like mine or the Mendix stories.
Did you use Epics or stories on this tab?
Make sure the right planning tool is selected.
And make sure the right sprint is active. Example beneath in Mendix stories.
Hope this makes some things a little bit clearer
You can create the stories in Mendix Sprintr
Soved it by re importing the storied in active sprint , Some how my stories were not linking to the epic . Thanks