The checkboxes that change a ticket's properties do not have a None option in the Team selection in order to unassign Agent Team
Respuesta oficial
Christine Loh
We are glad to inform you that this feature is currently available. When replying to a ticket, you are now able to select the Team checkbox and in the drop-down menu, select Unassign Team. Once you send a reply, the Team will be set as Unassigned.