The URL is still a page, only the template used has probably changed.
The sidebar is obviously displayed by the Astra theme you are using. They have documentation on this here: https://wpastra.com/docs/sidebar-free/
If you have any further questions, I would recommend contacting their support: https://wordpress.org/support/theme/astra/
Thanks, @threadi. I know of the Astra sidebar settings. I’ve tried switching off my plugins. It really was out of the blue, and I have been in and out of those pages both via admin WP, Elementor, and as a visitor on the front end. It’s never (from memory) happened before on an WP install I’ve had, and it has happened to another page –
https://www.thepeoplescientist.co.uk/privacy-policy
and both of those pages, whilst being listed in Pages, appear as a blog.
This page is ok – https://www.thepeoplescientist.co.uk/bridging-the-workforce-skills-shortage-gap-in-scottish-smes/
I don’t want to enter any pages now, in case they get turned into posts.
I’ll try to set up a new page. I will also use a plugin to convert a post to a page or vice versa and see if that gets it back to normal. I might switch to a different theme.
Sorry if I am missing the obvious here.
Thanks
So, I’ve gone with the delete and replace option and the Services page is back to appearing like a page. Let’s hope it was a glitch. If it stays like that, I will replace the couple of other pages that aren’t quite happy with the binary state of WordPress and feel the need to be a bit of both.