1. Right-click on the extension icon and click options and copy your license key and paste it in a place you will remember like a notepad doc on your desktop.
2. Right-click the extension icon and click remove from chrome
3. Click Remove in the popup
4. Go to this link https://chrome.google.com/webstore/detail/how-many/fifaampimdjablpkjapdjehjcfloecjp?hl=en-US and click add to chrome.
5. Click options again and paste in your license key and click save