Corrupted pages.

Dear members,
Just encountered an issue with the Theme Circumference Lite. I had a page open whilest updating to the latest version. This page is now somewhat corrupted. This means, the visual editor changed into text. And this stays like this on the live website.
Wanted to add a new page and delete the corrupted one, however when updating the page – the text changes into a corrupted one again.

Can anyone help? Many thanks.

Here’s a link:
http://www.engelenfengshui.nl/engelen-feng-shui-consulten/werken-met-allure