It is not advised to delete an agent profile, as you'll lose track of tickets that were assigned to the agent. Instead, it would be better to convert the full-time agent into an occasional agent.
This way, you will free up an agent seat and you can retain the record of tickets assigned to the agent. If you also want to make sure that the agent doesn't login again, you can edit the email address to a dummy email address like this: xyz@example.com.
Please follow the below steps to remove an agent from your helpdesk:
1. Go to Admin > Team > Agents, and click on 'Edit' corresponding to the required agent name
2. Choose the 'Occasional agent' radio button under Agent Type
3. Change the email address to a dummy email address if you do not want that user to login in the future
4. Hit 'Save'
Pro Tip - Before deleting the agent, assume their identity. Please navigate to the Tickets page and filter all tickets (open, closed, pending, resolved, etc.) that are assigned to that agent and do a Bulk Action to re-assign them to another agent. Then, you could delete the agent without having to worry about which unassigned tickets were originally assigned to them.
Note: The impact of deleting an agent is that all tickets assigned to that agent will automatically be unassigned and the agent will be converted into a customer in your Freshdesk account.