thanks again for your help! I did some changes:
This https://www.holidayomat.com/en/holidays-australia/au-2017/ i did change from page -> post. Also i did add tags and now it will work!
Also i did install plugin “Tag Pages” which make it possible to add tags to pages. That i did here https://www.holidayomat.com/en/holidays-australia/ Tag “Holidays Australia”
Also i did tag this post https://www.holidayomat.com/en/holidays-australia/adelaide-cup/ with Tag “Holidays Australia”
But on this sites it will not work perfect!?
Can you have please a look.