You may want to update the content that appears when sharing your page via Facebook or Twitter.
How to get there:
Login to your Wizathon back end account.
Click on the "Setup/Tools" tab.
Click on "Manage Website Settings".
What to do:
Scroll down to the heading titled "Social Media" and edit the description.
Click "Save Event Website Settings" to maintain your changes.
If the change does not appear on Facebook's end immediately, their cache simply may not have cleared in a while.
Go to https://developers.facebook.com/tools/debug, enter the Wizathon site, and click Debug.
If you do not see your changes, click Scrape Again.
This will force Facebook to update the cache and display the most current website information.