Where did you have this issue? On custom form in SharePoint site or in a standalone app? I cannot reproduce your issue. Once I ordered the data cards inside the form and save the app, next time I play the app, the order is correctly shown.
Please share more details and take a screenshot of your issue if possible.
Community Support Team _ Mona Li If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.