You may have to do a “hard refresh” of a page in your browser if you have an out of date, cached version of that website.
While on the problematic site use the key combination below to trigger a hard refresh depending on your operating system:
CTRL + F5
Apple + Shift + R or Command + Shift + R
To learn more about this read: http://refreshyourcache.com/en/cache/
If a hard refresh doesn’t work, try opening the problematic page in your browser’s private browsing mode.