Minimatica-Suddenly Post won't sticky to Front Page

This is driving me a bit bananas.
I have been using this theme for a long while now. I just posted something new a week ago, ‘sticky’d it to front page so it showed in the home page slider. No problems.

I have updated a post, gone through the same actions I have many times in the past and for some reason, this time, it won’t sticky. I have checked the date, time, publish, checked off the ‘sticky to front page’ button. Basically I have copied the other stickied posts identically (except for date) and it just won’t sticky.

Suggestions?

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