I have a visualization with a dual axis, with one axis showing bars and the other showing two lines. It shows up as expected on a desktop, but users who have smaller devices are not seeing the second line (the red one). I've tried synchronizing/un-synchronizing the axes, adding more and less space to the visualization on the dashboard, and adjusting the thickness of the line, but I still can't get the red line to show up on a mobile device. Are there any tricks to force all marks to appear regardless of screen size you're viewing the visual on?
Do you have a workbook with sample data that you could share? Also, does the issue occur in the Device Preview mode on desktop?