I migrated a Jira site from server to cloud. Weirdly, not all the attachments are available on the cloud site. The ones which have not made it to the cloud site have been made / uploaded in 2010. The later ones are available (though there is no way to verify this, there are way too many attachments in the site). When I click on those, I get something like this.

Does anyone know why this might be happening?