WD2000FYYZ-01UL1B1 and half space

Hi. I have 8 disk WD2000FYYZ-01UL1B1, that was stay in the server. few day ago i checked space and 6 of them show that they have 2TB space, but 2 of them show only 1TB space.
I wrote about it to the support of WD, but nothing is done.
I think, that I need update fw in the broken disks, but download new/old/stable/another of my fw I cann’t because fw for this disks is missing for download.
Where I can get stable fw? if it missing at all, that report me about it, please.
Thanks for your help.

Hi,

As far as I know this hard drive model does not a firmware download available from the Western Digital website.