"Whenever using the formular “Assign users to roles” in System administration the button “Manually assign / exclude users” cannot be used when a role merely has the user "Retail Service Account" is applied.

This is in my eyes completely randomly assigned to of roles.

This, unfortunately, inhibits the system admin to assign roles to a huge number of users.

However, this upcoming cannot be seen, once another user is assigned to this role: 

As there is a Microsoft document that inhibits us to delete the Retail Service Account" this functionality cannot be used although it is tremendously important to our customers.

The functionality of a(s)signing Users to a role is the most convenient way to assign roles to users.

This functionality is inhibited by the "Retail Service Account" which is not allowed to be deleted due to the MS rules.

Please, review this Bug and enable the Button "Manually assign / exclude users" in the "Assign users to roles" table to make the product more convenient for usage."