3D FlipBook - When re-arranging meta boxes on the edit page, the "Details" meta box goes blank (iFrame is empty)

Hi,

Thank you for your amazing work on this plugin, I have come across a bug which I can't seem to find any help with by looking through other questions in the forum.

This video shows what happens when you click the (^) or down (v) arrow on the 3D FlipBook edit page: https://drive.google.com/file/d/15Db0deCkMWlOB0ut5pwad9QcukyY2fVF/view.

The "Details" meta box becomes empty when the it is moved either upwards or downwards.

I have tried this on 2 different sites and have also disabled all plugins except 3D FlipBook and the result is the same.