Sorry to hear about this problem, however I don't believe that Atlassian has taken any intentional action here to remove backlogs here. It looks like an error has occurred on that page. I looked into your account, you are the site-admin of this Jira Cloud site.
At the time you posted this problem, it looks like your site was on the Cloud Free plan, in which case all support for Cloud Free is managed here in Community.
But since that time, it looks like you have started a Standard trial, which in turn will entitle you to support from our Atlassian Cloud support team.
So I would be interested to learn if this particular problem is still happening on your site first. If it is, then in this case, I think it would be best to create a support case for this problem, which you could do yourself now by going to https://support.atlassian.com/contact
I have created a new support case on your behalf here over in https://getsupport.atlassian.com/servicedesk/customer/portal/23/JST-551934
I fear that our Cloud support team will need to take a closer look at your Cloud environment to better understand the possible causes here.
Jira is a powerful tool that helps teams to plan, manage, and report on their work. We love using Jira, especially for its ability to track issue progress. But how to monitor the...
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