Disappearing symbols in Adobe Animate

[tizzue]

Good morning. I'm starting my adventure with animation and chose Adobe Animate. Unfortunately, I have a problem and I don't know what I'm doing wrong from the very beginning, I can't get an answer to this problem anywhere.
It's about errors while generating the movie. The drawn symbols disappear from it. Moving hands of the characters disappear in the animation during the preview and in the movie. Please help me, I don't know what I'm doing wrong and I'd like to avoid mistakes in the future. These symbols are drawn, it's not png

Cheers
Grzegorz Niewidok

[kglad]

most of the time, as best i can determine, it's user error involving tweens. that said, it's easy to make those errors.