I don't believe there is a cleanup interval for old accounts. You need to perform this cleanup. See below how to filter out inactive accounts, and delete them:

------------------------------
Dustin Burns
Lead Mobility Engineer @Worldcom Exchange, Inc.
ACCX 1271| ACMX 509| ACSP | ACDA | MVP Guru 2022
If my post was useful accept solution and/or give kudos
------------------------------