Try clearing out your browser's cache/browsing history. When you have done that, close out the browser and re-start it in a fresh session. If that doesn't do it, then try using a different browser.
Have done all of that, with no luck. Had a tech here for another reason a few weeks ago and told me there was problems with the fibre speeds. Told me they were within limits. I may have to call back the tech, still slow as heck.