Disks changed name because they were moved from the RAID controller, also because of that they fail to mount in the array due to not conforming to the partition layout Unraid requires, that's two of the reasons we don't recommend RAID controllers, you have two options, assuming parity is still valid you can rebuild one disk at at time so that the correct partition layout can be recreated, like this:
https://forums.unraid.net/topic/84717-moving-drives-from-non-hba-raid-card-to-hba/
Other option is to mount the disks with UD since it won't care about the incorrect partition layout and copy the data to new disks in the array.