Problem upgrading disks

[nitad]

Hi
Sorry if I post in the wrong board there is no "Troubleshooting".

I have a 3202T which had two 4T disks in Raid 1. One of the two disks gives a SMART error and I thought to myself that this is the occasion to change both! I replaced the failed disk with a WD Red 6T, after ten hours my volume with a 4T disk and a 6T disk shows "Good". I want to replace the second 4T drive with a new 6T. But it gives me the initialization page /? 5F82XXX
What to do next ?
If I start the NAS with only one 6T disk, i have no problem!
Thanks for your help

[orion]

My NAS is a hot-swappable model, so I can replace disk without shutting-down NAS. I think you can try the following:

• Remove NAS case. Turn NAS on (4T + 6T disks). Replace the other 4T disk with a new 6T disk without turning NAS off. After NAS is synchronizing volume for several minutes. You can shutdown NAS, put NAS case back. Then turn it on.
• Now your NAS should be ready with 4T + 6T disks. Turn NAS off. Remove NAS case. Remove the working 4T disk and move the working 6T disk to another slot. Yes, change the slot position. Then insert the new 6T disk to empty slot. Turn NAS on to have a try.