Workaround :

Run the restore and the Job would prompt for the correct Tape if it does not find it in the slots

OR

Check the Backup sets present in each Tape from Storage Tab and identify which backup set resides on which Tape

Symantec Corporation has acknowledged that the above-mentioned issue is present in the current version(s) of the product(s) mentioned at the end of this article. Symantec Corporation is committed to product quality and satisfied customers.
 
This issue is currently under investigation by Symantec Corporation. Pending the outcome of the investigation, this issue may be resolved by way of a patch or hotfix in current or future revisions of the software. However, this particular issue is not currently scheduled for any release.  If you feel this issue has a direct business impact for you and your continued use of the product, please contact your Symantec Sales representative or the Symantec Sales group to discuss these concerns.  For information on how to contact Symantec Sales, please see  http://www.symantec.com Please be sure to refer back to this document periodically as any changes to the status of the issue will be reflected here.