Adding Milestone flags into Line chart in power Bi

Hi bnadir55 ,

Thank you for reaching out to the Microsoft Fabric Community Forum and for sharing the screenshot. Also thank you burakkaragoz and GrowthNatives  for your helpful response.

The behavior you're seeing is expected and helps identify the root cause. The milestone diamonds are appearing on incorrect or multiple dates because the milestone logic isn't linked to the current X-axis date. Power BI detects that a milestone exists in the data, but not specifically on the plotted date.

This occurs because the line chart uses a continuous Date axis from the calendar table, while milestone data comes from the Tasks table. If the DAX doesn't check that Finish_Date matches the axis date, Power BI shows the marker across multiple dates.

To resolve this, the milestone measure should only return a value when the finish date matches the X-axis date, returning BLANK otherwise. This keeps milestones aligned with the S-curve.

After making these changes, you should see one diamond per milestone, placed on the correct finish date, and aligned with the S-curve. Also, make sure the X-axis uses the Calendar[Date] column, is set to Continuous, and there's an active relationship between Calendar[Date] and Tasks[Finish_Date]. This will ensure milestones display correctly.

Thank you.