It might be a caching error. Here is how to clear the cache for some of the major web browsers
Firefox
- Click the menu button
and select Options. - Select the Privacy & Security panel.
- In the Cookies and Site Data section, click Clear Data…
- Remove the checkmark in front of Cookies and Site Data.
- With Cached Web Content check marked, click the Clear button.
- Close the about: preferences page. Any changes you’ve made will automatically be saved.
Tip: Here’s another way to clear the Firefox cache:
Click the Library button 
, click History, and click Clear Recent History…. Next to Time range to clear, choose Everything from the drop-down menu, select Cache in the items list, make sure other items you want to keep are not selected, and then click the Clear Now button.
Chrome
- On your computer, open Chrome.
- At the top right, click More
- Click More tools
Clear browsing data. - At the top, choose a time range. To delete everything, select All time.
- Next to “Cookies and other site data” and “Cached images and files,” check the boxes.
- Click Clear data.
Safari
- Click on the Safari tab at the top right of your screen and choose Preferences from the dropdown menu.
- Click the Advanced tab of the menu that pops up.
- At the end of the tab, select the “Show Develop menu in menu bar” box and close the Preferences menu.
- Click the Develop tab from the Safari menu at the top of the page.
- Click Empty Caches from the dropdown menu.
You may also want to clear your browsing history in addition to emptying your cache. Here’s how to do that.
- Choose the History tab in Safari.
- At the very bottom of the dropdown menu, choose Clear History.
- A box pops up with a choice to clear the last hour, today, today, and yesterday, or all history. Choose your time frame and click the Clear History button.
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