Hello @Jim Millar
As it seems the mirror is been done by AOMEI you must check their forums for any troubleshooting steps that might help you in your situation.
First, you must understand the difference between the 'Break Mirror' vs the 'Remove Mirror'.
The "Break Mirror" operation, will stop the mirroring on the selected volume, without affecting the data on any disk. (Data will remain untouched on both disks).
The "Remove Mirror" operation, will stop the mirroring on the selected volume and destroy all the data on the mirror disk. (Data will remain only on one disk).
Know the Right Way to Resynchronize and Repair a Mirrored Set
Hope this resolves your Query!!
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