How to read manga properly in KOReader?

I am trying to read manga on my Kindle Paperwhite 7th Gen using KOReader, but it seems KOReader isn't handling the CBZ files properly, or I might be doing something wrong.

I have the original CBZ files. First, I open KCC, select my Kindle model, check Manga Mode, Spread Splitter, Stretch/Upscale, and Cropping Mode, and then reconvert the CBZ file according to my device. I also tested unchecking some options, but when I send the CBZ file using Calibre to my device and open the manga, it looks like this. Also, the Panel Zoom isn't working, even though the option is checked:


I also tested KOReader's margin and page fit settings, but nothing makes the manga look proper. I'm not sure what I'm doing wrong. I checked my original CBZ files, and they look completely fine. Please help me solve the issue. Thank you!