Older - 4tb G-Raid w Thunderbolt 2 Won't See 6tb Drives. What should I do? (Mac)

Hi, is anyone familiar with upgrading the G-Raid 4TB G-Raid w/ Thunderbolt 2?
I bought an enclosure (two unfortunately) and dropped in a pair of new 6tb drives to raid and they’re not seen in Disk Utility. The front light comes on, drives spin up and the device shows in the System Profiler as connected via Thunderbolt, but that’s it. Nothing in Disk Utility to format or mount.

Any help would be greatly appreciated.
Thanks FreQuenC

Hello,

We request you to check the below link to assist you for the drive is not detected in Mac OS:
https://support-en.g-technology.com/app/answers/detail/a_id/890