Hello Andy,
Thanks for submitting a question about changing the title on your page. If you have not already, I advise clearing your browser cache to make sure you are seeing the site as it is rather than a cached version of the page.
Likewise, your WordPress site may also have a caching system involved via a plugin or your server configuration. Clearing this information as well will be a good step to take.
If those do not work, let us know how you are trying to change the title or what steps you are following. This way, we might have a chance of reproducing the error on our end.
Best,
Christopher M.