Permanently deleting a user from your Zoho CRM account runs the risk of deleting the data and the history associated with the user. We rather suggest you to deactivate the user so that no one can log into the service using the deactivated ID. Moreover, only active users are counted for license so, you can add a user replacement rather than deleting.
To do this, please send us a request at the Zoho CRM support for replacing the user ID by a new ID (which does not have any user account in our Zoho CRM service) with the following details:
However, permanently deleting a user is possible if there is a single user in your Zoho CRM account. In which case you need to send a request to the Zoho CRM support with the following details: