Convert Manga in Mobi to Epub Format

I try to merge some chapter of manga with Mobi extension. I had found the only way to merge it with calibre is using plugin Epubmerge. I had to convert mobi file to Epub the merge it then convert merge file to mobi. My problem is every time i convert from mobi to Epub the page become split to two page. Any suggestion how to convert the mobi perfectly or to merge several mobi file to one mobi file.
I attach some file to support my question

1. Original file (Mobi)
2. Conversion Log (txt)
3. Output file (Epub)
4. Screen capture of the problem

I dont see any error report and conversion option still in default

Thanks

Attached Thumbnails

 

Attached Files

	One_Piece_004__Marine_Lieutenant_Axe_Hand_Morgan.mobi (3.63 MB)
	One Piece 004_ Marine Lieutenan - Eiichiro Oda.epub (1.86 MB)
	conversion log.txt (9.4 KB)