Attempts to reply to two articles today, both gave this error. The first seems to be working now, but I think that’s due to the way I’m navigating to the article?
Just now (which is the second article), I tried to click the “Be the first to comment on this article” button at this page: https://www.choice.com.au/home-and-living/kitchen/benchtop-cooking/articles/should-you-buy-a-multi-cooker and it took me to this page: https://www.choice.com.au/error_500.html?aspxerrorpath=/submission-container
Instead, if I instead go to a post about that article, here: Should you buy a multi-cooker or slow cooker? and then click the “Reply” button, it works just fine, and lets me create a post without the error.