When you start working on a ticket assign it to you first, before taking any action. Every ticket must have an owner.
The ownership of this ticket is not permanent you must un-assign the ticket at the end of your shift.
You should not have any ticket assigned after your shift is over.
Example (European time):
Francisco FM shift: 9 am to 5 pm
Sabrina M shift: 1 pm to 9 pm
Celeste S shift: 2 pm to 10 pm
Ticket A: Francisco will be the owner until 5 pm, Sabrina will be the new owner from 5 pm to 9 pm and Celeste will be the last owner until 10 pm, having to transfer the ownership to Francisco, who is the agent that will start the day at 9 am.