Hi @drchrisd thank you for your post here on the Zoom Community! When you start a cloud recording, the recording is tied back to the host's account, even if you were designated as a co-host and started the recording. So we need to have the host log into the Zoom web portal and take a look at the recording.
Each recording will have a "Share" option (this can be disabled by the account owner/admin but if it was shareable in the past, this must be allowed) and the host can configure how it is shared. One option is an expiration date, it is possible the recording share is set to expire, that is the most likely cause. Here is a screenshot from my Zoom web portal, after I went to Recordings and clicked on the "Share" option on the far right side

If you have your host re-share with a new or no expiration date you should be good to go!
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