Caching is a technique used by browsers, websites and web servers to save regularly used files to prevent them needing to load again, therefore speeding up loading of the page.
Sometimes files and content change, and your browser may not always pick up there there is a change.
First you can try opening in a new private window, or a different browser. If the issues remains, you may need to clear your browser cache. Please note, you don't need to clear your cookies, just your cache.
Here's how to clear your cache:
Google Chrome
https://support.google.com/accounts/answer/32050
Mozilla Firefox
https://support.mozilla.org/en-US/kb/how-clear-firefox-cache
Microsoft Edge
https://clear-my-cache.com/windows/microsoft-edge.html
Apple Safari
https://www.businessinsider.com/how-to-clear-cache-on-safari-browser?r=US&IR=T
Apple iOS Safari
https://support.apple.com/en-gb/HT201265
Android