Due to some updates over the weekend to issues.unrealengine.com (our public bug tracking site) approximately 1,000 tickets were dropped from visibility, and then later restored. Unfortunately the Voting data was lost in the process, meaning some users who may have been tracking these issues in their voted list will no longer have these tickets listed. In this case, you will need to search for the issue again and re-vote on it. The other approximately 5,000 tickets on the website were not affected.
We apologize for any inconvenience, and are working to ensure no loss of data in future updates.