HTML5-Export results in blank white page

Hey!
I got a Animate Project (HTML5 Google Ads box) to edit and export. When i wanted to publish the file, the html didnt display anything - just blank white.

When i created a blank project and drew something random in and published it the same way - my drawing showed up. Then i even copied the layers of the original document into the one where the export wored - still the same results.

What could be wrong? I am fairly new to Animate so i hope someone can help. It surely is just a minor fault of mine.

Thanks!