1. Click on hamburger icon.

2. Click on dashboard tab and open Line Chart in edit mode.

3. The Edit menu box appears as you click on Line chart icon. And a widget gets added in content place automatically in dashboard.

4. In Formatting Property click on General. In General click on Global Thousand and Decimal Separator Property.

enable Toggle of the Thousand Separator, As Shown in below figure

7. Click on Preview and Save and Exit.

8. Now, match your Line chart with the below example, it should look like the figure below: