google apps script - Unable to create an event for calendar -

i trying create events dynamically based on data. able achieve using calendarapp. now, want add room event when event created. that, trying create event calendar of particular meeting room. calendar of meeting room using

calendarapp.getcalendarbyid(calendarid); 

however, unable create event it. above line able retrieve calendar(its not null). however, when try add event via calendar.createevent gives me error saying 'action not allowed'. have subscribed above calendar. have tried using calendar.calendars.get(calendarid); retrieve calendar , calendar.events.insert(event, calendarid); add event it. however, result same. missing? not have admin rights room's calendar. reason? if yes how solve it?

achieved subscribing calendar resource want book via calendar settings mail id going using , adding resource's mail id guest in invite. thank zig help!