Hello,
Did the issue start after adding a new hard drive to array?
Meta data from hard drive used in different MSA could create ghost disk groups/pools.
if this is an unit in production, I would suggest logging a case with HPE and get the logs reviewed before proceeding further.
You could use submit a case or chat with HPE options under "Cases" at the following link to log a support case:
https://support.hpe.com/hpesc/public/home