Hi Connor, that sounds like a definite problem. Confluence's behavior when encountering an uninstalled macro on a page is to show that Unknown Macro error. Since this is a default Confluence module (the Tasks), I think what has happened here is that during the last restart of your Cloud instance, the Task's module failed to load. You may be able to find this in your Manage Add-ons section of Confluence, I'm not sure it will be useful to look though. It should look something like this:
Since you are an Atlassian Cloud customer, you're entitled to support at support.atlassian.com; this is likely the best route for you to take for a fast resolution.
Bug reported here: https://jira.atlassian.com/browse/CONF-40441
Connect with like-minded Atlassian users at free events near you!Find a group
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no AUG chapters near you at the moment.Start an AUG