You either have corruption in the database - or SAN issues causing problems.

First, run the following (when you can - not during business hours): DBCC CHECKDB ({your database}) WITH no_infomsgs, all_errormsgs;

If that reports errors, you will need to get those fixed as soon as possible.

If that does not report any errors, then you need to work with your storage team to see if there are errors on the SAN causing SQL Server to think the data has been moved.