I wiped the disk using
wipefs -a /dev/sda.
I happily formatted the disk, and it seems that when I'm about to mount /dev/sda3 it says "unknown file system type crypto_LUKS".
I did no encryption on this partition, so it's like the previous configuration is saved somehow. If I apparently wiped or reset the disk, how can this be possible?
Do I have to open and decrypt and remove encryption on that drive first?