If you are unable to automatically add JIRA Software, JIRA Core or JIRA Service Desk to your site, you may face the below message when attempting to start a trial on an existing Confluence cloud site
We're upgrading our cloud infrastructure to make your Atlassian experience even better. During this change, you won't be able to automatically add JIRA Software / JIRA Core / JIRA Service Desk to your site.
Please raise a ticket with our Support Team so we can add this application for you.
If you've come across this messaging, watch this ticket to be updated when JIRA will be available to be added to your existing site