Scheduled Post Error

Hi I am having issues with scheduling my posts.
I post weekly.
One was scheduled for this morning 7am. With my newsletter going out at 9am. However the link in my email didn’t work. And when I logged into to check – it says it missed its schedule – so it didn’t get published at all.

And I recalled my 2 weeks ago post, same thing happened, I thought it was my fault and that I put the wrong date to schedule, but it happened twice now, and I don’t think its me.

In addition, the shortlink doesnt seem to work on instagram i.e. when I put it on profile “Website” it cannot be saved.

Appreciate your advice.