Server-side texture packs not working

For some reason when I try to add a server-side resource pack. The server and texture pack are on minecraft 1.20.4, but only 1.20.3 clients get the pack. Joining on 1.20.4 doesn't give anyone the pack. The server also says this in the log at the start, not sure if it's relavent to this issue though:

resource-pack-id missing, using default of bc405632-fece-378d-af08-fd0c908bafa1

How can I fix this / figure out what's wrong?
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