When you view a website your browser will store a copy of the contents of the web page (images, videos, text) and keep a copy on your computer hard drive or device. This helps increase the page load speed, so next time you visit the page, it remembers the previous page content.
Sometimes, when you make a change, or if fixes have been made, you will need to clear your cache to remove the saved content from your browser. You will then be able to view the updated page, rather than the cached version.
Each version of the browsers you use will have a different way to locate the setting you need to clear your cache. Usually this will be found in the browser settings / history.
Here are 2 links to useful websites that will help you to locate the setting depending on your browser. These are updated regularly, which is helpful because there are lots of browsers to choose from!