Clearing my browser cache did the trick. Appreciate all you advice though.
Thank you threadi. That’s the article I read. It’s just over my head I’m afraid.
My server, Namesco, stated that it’s not a problem their end, but I will try and go back to them with this new advice.
15 years ago I set up and ran my own website very successfully. The systems have all changed dramatically now, and apparently are so much easier to set up and maintain. But this new website has given me so many problems.
Thank you for your messages. Much appreciated. I don’t have much technical knowledge, and I have no idea how to ‘enable WP-DEBUG’. I have Googled that process, but I still cannot work out how to do it. And I can’t find an ‘error log’. Where is this?