When you say a "PDF file" isn't showing up, what exactly do you mean? Can you share some screenshots (here or in an email to support@zotero.org with a link to this thread) that show the item in the web library and what you see on iOS?
It's a new problem that's only affecting a collection created recently ('PgDL'). The subcollections ('Admin & HR'; 'Equity & Trusts'; etc) and the subcollections within those ('Textbook'; '4 Conflict of Rights' etc) do appear on all devices.
But the items within those subcollections are generally not showing up on the iPad (iPadOS 26.3); the only ones that appear are those that have been annotated. This is continual - if I annotate something new, it will show up on the iPad.
This issue does not affect Zotero on my phone (iOS 26.2), and has not affected older subcollections and their items.
I attach screenshots, interleaving the problem-free desktop ones with the iPad ones where items are missing.
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It's a new problem that's only affecting a collection created recently ('PgDL'). The subcollections ('Admin & HR'; 'Equity & Trusts'; etc) and the subcollections within those ('Textbook'; '4 Conflict of Rights' etc) do appear on all devices.
But the items within those subcollections are generally not showing up on the iPad (iPadOS 26.3); the only ones that appear are those that have been annotated. This is continual - if I annotate something new, it will show up on the iPad.
This issue does not affect Zotero on my phone (iOS 26.2), and has not affected older subcollections and their items.
I attach screenshots, interleaving the problem-free desktop ones with the iPad ones where items are missing.
https://s3.amazonaws.com/zotero.org/images/forums/u8016739/sqdol1ymmi931rxpfuc2.png
https://s3.amazonaws.com/zotero.org/images/forums/u8016739/kazl1715svijizgp1m38.png
https://s3.amazonaws.com/zotero.org/images/forums/u8016739/8jjr9p9kv5eah4m2ovdh.png
https://s3.amazonaws.com/zotero.org/images/forums/u8016739/gaj9lff7n5fhsiuuvwbh.png
https://s3.amazonaws.com/zotero.org/images/forums/u8016739/772yg8zdjhjbswho7zk6.png
https://s3.amazonaws.com/zotero.org/images/forums/u8016739/sq36jyfb3hugseobni39.png
https://s3.amazonaws.com/zotero.org/images/forums/u8016739/dcn96zzrk70ufwottmqa.png