Some files in IPFS share aren't accessible?

Hello! I’m trying to retrieve some files over ipfs. I’m very new to this.

This is the specific hash I’m using: bafykbzacedu754nwrihlskqi4kjssv6d2qebx73bsmwnillzn2fu7cvnludu4/ISO/10001-15000/

When I access some PDFs from there, some work fine (ie. ISO 13846-2000.pdf) and some don’t work, and fail with an error 524 (ie. ISO 13849-1-2015.pdf)

How are these different? Why would some work and others not work?

I’ve tried in a browser, the desktop client, and the cli, each with different, but equally negative results