Card Font Size

Hi Chrisss14 ,

Can you provide us with your Power BI Desktop version number? It is true that in some versions the criteria of json has been changed. let's check if the version is the cause of the problem.
Solved: Custom Theme Import Errors - Microsoft Fabric Community
Solved: Re: Custom themes are broken - Microsoft Fabric Community
Also, some themes do have limitations on the size of the fonts, so you might want to try changing themes to see if that's possible.
Use report themes in Power BI Desktop - Power BI | Microsoft Learn
If none of these methods work, try using a text box. Text boxes support a maximum size of 96.
Solved: Card Visual - Font size need 80+ - Microsoft Fabric Community

Best Regards,
Dino Tao
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