Hello

I am trying to convert .epub file into .mobi file using ebook-convert. I need new mobi version (KF8). After conversion, the mobi file opens on my computer. However, when I transfer it to my Kindle (Kindle Paperwhite 4), I get the following message:
Unable to Open Item
The selected item could not be opened. If you purchased this item from Amazon, delete the item and download it again from Cloud on Home.
Has anyone else had this problem, and how can I get around it?
Both the input and output files attached.
The command I use:
ebook-convert in.epub out.mobi --dont-compress --mobi-keep-original-images --mobi-file-type new