Charles -
It seems that the drive is missing, which is why I gave you steps to recover it.
This is why I don't recommend RAID, after seeing countless cases in forums for 14 years where when one drive fails the data is lost - even in a mirror RAID. https://www.pugetsystems.com/labs/articles/Why-...
For RAID0 showing wrong size in Windows:
https://forums.tomshardware.com/threads/bios-ra...
https://forums.tomshardware.com/threads/raid-0-...
https://community.intel.com/t5/Rapid-Storage-Te...
I would ask for more help from the best hardware forums Tom's Hardware here: https://forums.tomshardware.com/ as they specilize in this while we do not.
Feel free to ask back any questions. Based on detailed results you post back I will have other suggestions if necessary.
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