If you installed your #ubuntu with full-disk #encryption a while, you may want to upgrade your #luks header version to enjoy improved #security and stronger password hashing algorithms.
You can't change LUKS header from a live system - you need to boot a live Ubuntu USB to be able to access the encrypted partition. First, create a bootable USB stick using a regular Ubuntu installer image.
- Just get the latest installer ISO available
- You need the full installer, the mini network installer won't work
- You may need to disable Secure Boot in BIOS temporarily to boot from USB