Sometimes a web page that you have visited previously will not show the latest version, because the old version is cached in the browser.
You can force the browser to refresh the page by doing a 'hard refresh'. Instructions for the different operating systems are below:
On a Windows device: ctrl + F5
On a Mac/Apple device: Apple + R or command + R
On a Linux device: F5
However, sometimes a hard refresh won't work and you will need to clear the browser cache manually.