SD-WAN API: enable in "role" not possible

In GUI Zscaler Cloud Portal - Role Management (zscalertwo.net), I go to “Role Management” and try to create a new SD-WAN role (in Partner Management, SD-WAN has been enabled for a partner).

But if I wanted to enable “SD-WAN API Partner Access”, this is greyed out, i.e. not possible. And if I try to use the Restful API in order to retrieve “Locations”, it consequently fails to deliver any location.

Screenshot attached.

Meanwhile, I learned from a ticket that this is a feature, not a bug.