Lottiefiles plugin for AA doesn't show animation preview

Hello,
I have a problem with Lottie FIles plugin for adobe Animate. I created simple animation (for create I used svg) and wanted to save as lottiefiles or .json. Plugin doesn’t show me preview and after save it looks like empty. What I do wrong or how can I fix it?

I’m experiencing the same issue. Only previews the first frame.