Missing/not downloading all chapters

[Robin-Sch]

Describe the bug

Whenever I add a new manga, it does not download all chapters for some reason (and it does not give a clue about missing chapters). For example, with Skip and Loafer it doesn't download chapters 53-55, but it does download 56.

Also, sometimes it doesn't list the correct amount of chapters (for example with Horimiya it says there are 66 chapters, whilst on mangadex there are 126. With the second "mangadex" source it shows 155 chapters tho??).

Reproduction steps

1. Find a manga of mangadex
2. Check the amount of chapters on mangadex
3. Add it in kaizoku
4. Notice that not all chapters are downloaded, and some are skipped

Expected behavior

It should download all chapters, or at least show that some failed/are missing?

Additional context

No response