Hi @StevenZhang ,
Could you please share a bit more about your scenario?
Could you please share a screenshot about your issue within your published app?
Do you mean that the Auto-Height property of the Label in your Gallery could not work as expected?
Based on the issue that you mentioned, I have made a test on my side, and don't have the issue that you mentioned. The Auto-Height property of the Label works well in my published app.
Please consider run your published app using different browsers, then check if same issue would occur. My PowerApps version is 3.20023.8, please make sure you create your app using the latest version of PowerApps.
If the issue still exists, please consider insert a Normal Gallery rather than a Flexible Gallery in your app, then add a Lable into this normal Gallery and enable "Auto Height" property, check if the issue is solved.
Best regards,