Posts are all failing as of Tuesday 28 May

Posts are all failing as of Tuesday 28 May

I get the message:  Here's what went wrong: 
Twitter Profile: Sorry, we couldn't publish this. 
Facebook Page: Sorry, we couldn't publish this. 
Instagram Profile: Something went wrong with Instagram. 


It was working fine before this.

What is wrong with it? This is a very critical time for our marketing so we need this to be working.