It seems that trying to clone a section with a sticky element (apparently) does not clone it.
Taking advantage of this bug, I will contribute another one with a small test that I have carried out:
If instead of cloning (which doesn't work) I do an export-import, the lottie doesn't import it (I don't know if it's because of the lottie itself or because it's a sticky).
I just checked in the front and really, when I did the export-import thing, if the lottie had been imported but it is not displayed in the preview of BeBuilder, but it is in the front.
You can do the tests you need in COPY HOME (I did the example of the video in another page that is not the one I have for you, but you can replicate it without problems).
PD: If I remove the "lottie element" and recreate it it works fine. But it seems that when exporting-importing section than contains lotties, the lotties they behave in an erratic way.
Thank you for reporting.
I have passed it to the dev team, and we will take a closer look at it.