how to delete an inactive account which are not visible in security console but present in IDCS

Summary:

we need to delete all inactive accounts that have been inactive in the last 6 months.

From our report showing all inactive accounts, we understood that there are two types of accounts: some inactive accounts are shown in the Security Console as "inactive", and other ones that aren't in the Security Console; both are inactive on IDCS.

We tried to delete two inactive accounts by uploading an HDL with User.dat:

METADATA|User|PersonNumber
DELETE|User|00XXXXXX

The file we tried to delete one inactive account that was not present in the Security Console and another one that was present in the Security Console as inactive.