Hi
No you just need to reset jDownloads as described inhttps://www.jdownloads.net/documentation-for-v3-9/getting-started-v3-9/reverting-back-to-jd3-2
The problem is caused by a database indexing and this depends on which version of MySQL or MariaDB you web host is providing.So we are rewoworking the upgrade to avoid the issue
Colin