JNCEP doesn't appear to be downloading epubs anymore

[Einhander1]

Describe the bug
Instead of getting the Epub files I get this.
Some of the requested parts are not available for reading!
Success! EPUB generated in 'E:\Books\JNCEP\Sorry_Darling_but_You_Won_t_Kill_Me_Again_Volume_1_Part_1.epub'!
Logout...

Expected behavior
Download ePub files

To Reproduce
C:\Users*******>jncep epub https://j-novel.club/series/sorry-darling-but-you-won-t-kill-me-again

Take care to hide your J-Novel Club credentials! This issue will be visible to everyone.

Debug trace
2026-07-10 09:00:09,843 jncep.utils WARNING Login to J-Novel Club with email '[highlight]7********@m******.com[/]'...
2026-07-10 09:00:10,326 jncep.jncapi DEBUG API J-Novel Club GET /app/v2/me params=None body=None skip=None
2026-07-10 09:00:10,371 jncep.utils INFO Logged in to J-Novel Club with email '[highlight]7********@m******.com[/]'
2026-07-10 09:00:10,371 jncep.utils WARNING ...
2026-07-10 09:00:10,372 jncep.jncapi DEBUG API J-Novel Club GET /app/v2/series/sorry-darling-but-you-won-t-kill-me-again/aggregate params=None body=None skip=None
2026-07-10 09:00:10,424 jncep.utils WARNING Get content...
2026-07-10 09:00:10,425 jncep.utils WARNING Some of the requested parts are not available for reading!
2026-07-10 09:00:10,426 jncep.jncapi DEBUG API J-Novel Club EMBED /embed/v2/PRT-5L3ZCRQ/data.xhtml
2026-07-10 09:00:10,426 jncep.jncapi DEBUG IMAGE https://cdn.j-novel.club/pub/img/480/jpg/01K/W/A/G03XBYWFXR4RG5HT0JZMG.jpg
2026-07-10 09:00:10,427 jncep.jncapi DEBUG ('PRT-5L3ZCRQ', 'data.xhtml') in events
2026-07-10 09:00:10,492 jncep.jncapi DEBUG IMAGE https://cdn.j-novel.club/pub/img/1200/jpg/01K/W/A/H7X3TFA70H5JEJYBCQHA6.jpg
2026-07-10 09:00:10,492 jncep.jncapi DEBUG IMAGE https://cdn.j-novel.club/pub/img/1200/jpg/01K/W/A/H3NX0T29MBH6TH01GHGVS.jpg
2026-07-10 09:00:10,493 jncep.jncapi DEBUG Cache hit ('PRT-5L3ZCRQ', 'data.xhtml')
2026-07-10 09:00:10,497 jncep.core DEBUG The hires cover candidate url doesn't look like a cover URL
2026-07-10 09:00:10,497 jncep.jncapi DEBUG ('https://cdn.j-novel.club/pub/img/1200/jpg/01K/W/A/H3NX0T29MBH6TH01GHGVS.jpg',) in events
2026-07-10 09:00:10,671 jncep.jncapi DEBUG Cache hit ('https://cdn.j-novel.club/pub/img/1200/jpg/01K/W/A/H3NX0T29MBH6TH01GHGVS.jpg',)
2026-07-10 09:00:10,856 jncep.utils WARNING Create EPUB...
2026-07-10 09:00:10,858 jncep.namegen DEBUG parse = {'t': [('legacy_t', [])], 'n': [('_t', []), ('str_filesafe', [])], 'f': [('legacy_f', [])]}
2026-07-10 09:00:10,858 jncep.namegen DEBUG Apply rule: legacy_t with args []
2026-07-10 09:00:10,858 jncep.namegen DEBUG Apply rule: str_filesafe with args []
2026-07-10 09:00:10,859 jncep.namegen DEBUG Apply rule: legacy_f with args []
2026-07-10 09:00:10,976 jncep.utils INFO Success! EPUB generated in 'E:\Books\JNCEP\Sorry_Darling_but_You_Won_t_Kill_Me_Again_Volume_1_Part_1.epub'!
The email (J-Novel Club login) will appear in the trace, so delete it if you don't want to make it visible.

Environment (please complete the following information):

• OS: Windows 10
• Python version: 3.8.8
• JNCEP version: v51

[gvellut]

• Using my credentials, I tested the command jncep epub https://j-novel.club/series/sorry-darling-but-you-won-t-kill-me-again you indicate. It downloads and the epub opens fine with the 3 available parts of the series.

• From the log, I see the tool downloads the Part 1: Isn't the epub valid with that part? Part 1 is always available no matter the subscription level so you will always be able to see it and jncep will always be able to download it and generate an epub from it.

• So are you sure your credentials have the right for the 3 parts of the series? Check https://j-novel.club/series/sorry-darling-but-you-won-t-kill-me-again. Make sure you are logged in and try to open Part 3 (available only with a paying subscription with the right level) in the web page with the online reader. Then report.

[gvellut]

One more thing: If you are a trial user, there was a fix in later jncep versions (newer than the v51 you indicate in your report; current version is v55). You may want to try the command with it (you will need to install a newer Python version ie min Python is 3.9 for that version and your Python 3.8 is too old).

You can also use uvx for launching see https://github.com/gvellut/jncep#alternative-with-uv