Can't Find the owner type option when editing a copied flow pattern.

I want to specify a task owner for each task within a copied flow, but once I copied the flow and go to tasks and select one to edit it, there is no option to attach a task owner.

I can only see that option when I try to create a new flow.

according to the below Link, I should be able to edit a Flow and attach an owner type to a specific task, but I can't see the option.