First, have a look at the page via ‘Preview’.
Can you now see the change you made?
Yes: the problem is probably related to site caching, see below. It may take up to 4 hours for your change to be seen.
No: the problem is probably related to how you made your change. Contact website@courtauld.ac.uk and report the problem. We’ll have a look at it for you.
See also:
My new page is not showing: how can I clear the cache?