By default, the assignee field has an unassigned option, which is equivalent to making the field optional. If you check out field configuration, you would realize that you cannot make the assignee field required, as there is no such option available.
In this recipe, we will look at how to disable the unassigned option, effectively making the assignee a required field.
You cannot disable the unassigned option if you have:
Proceed with the following steps to disable the unassigned option:
As shown in the following screenshot, once the option is disabled, issues can no longer be unassigned: