To add to this, that message usually appears when the system can’t locate the encrypted drive after you enter the password. It often means the boot configuration no longer matches the actual disk.
If there’s nothing important on the install, the safest route is to back up what you need from a live USB and do a clean reinstall. That avoids low-level recovery steps that could make things worse, and I wouldn’t feel comfortable giving those commands here. You’re of course free to troubleshoot it yourself and share any confirmed solution.
If you’d rather try recovering it, the next step is to grab the rdsosreport.txt file from the emergency prompt and post it here. That shows exactly what the system is complaining about without changing anything on the disk.
Reference: