outlook for mac can't show attendee

Question

On mac we create a Calendar event by script. The script is

tell application "Microsoft Outlook"
        set newAppointment to make new calendar event with properties {subject: mName, start time: mStartTime, end time: mEndTime, location: mLocation, plain text content: mDescription}
        set theListCount to length of emailList
        if theListCount is greater than 0 then
          delay 2
        end if
        repeat with i from 1 to count emailList
          make new required attendee at newAppointment with properties {email address:{ address: item i in emailList}}
        end repeat
        activate
        open newAppointment
    end tell

Run this script, the event is opened with the parameters expect attendee enter image description here While restart outlook, the attendee will show normally.

Why attendee no show before, and how to fix it expect restart outlook

I want to know the reason and to fix it