According to Diablo II: Resurrected - 9.24 Update
Furthermore, our team is working to resolve the issue of character lockouts. Many of these characters are already in the process of being unlocked. We anticipate this process will take a few hours to complete.
Curious why it takes a few hours for this process. Are they having to do this manually or something? Or a script that is just really slow with a lot of affected characters?