Format Painter and Custom Power BI Themes

Hello, 

I'm having issues with using the format painter with a custom Power BI theme I imported. 
I made a custom theme using a JSON file that would encompass the exact hex codes and font families my customer requires for reporting. The theme imported successfully, however, when I use the 'Format Painter' option on any visual I get this error: 

Then I'll click 'cancel' and the popup message will keep coming up. I need to go to my task manager in order to force quit the app. My team and I have found out this does not happen when using the default theme. 

Could you please tell me why this issue keeps occurring?

I'm currently running the Feb 2023 version of Power BI.