"Enter Reason" Pop-up in Mobile Customization for AP301000 "Bill And Adjustment"

I am working on a mobile app customization for the Bill and Adjustment (AP301000) screen. I need to display a pop-up for the user to enter a reason when they reject a document.

I have tried the following customization:
update screen AP301000 {
    add container "EnterReason" {
        add field "Reason"
        add recordAction "EnterReason" {
            behavior = Void
            redirect = True
            redirectToContainer = "EnterReason"
        }
    }
    update container "DocumentSummary" {
        update recordAction "Reject" {
            behavior = Void
            redirect = True
            redirectToContainer = "EnterReason"
        }
    }
}

 

Issue:

When I press Reject, the "Enter Reason" screen appears, and I can see the Reason field. However, I do not see the OK and Cancel buttons on the screen, which prevents the user from confirming or dismissing the action.

Expected Behavior:

• When the Reject button is clicked, a pop-up should appear with a Reason field and two buttons: OK and Cancel.

• Clicking OK should capture the entered reason and proceed with the rejection.

• Clicking Cancel should dismiss the pop-up without rejecting the document.