Steps to update your system.

1. Goto settings->update
2. Select the version you want to update from here.
3. First select update zip file and hit install update button. After the success message Hard refresh(Most Important) your browser.
4. If there are any additional zip file then select an additional zip file and again hit install update button. After the success message Hard refresh(Most Important) your browser.
5. Must check your application settings after update is successful. That's it.

If you get any error after update then go to yourdomain.com/settings/migrate 
If still error not solved then contact support team.

Note: Update your system in sequence like version 1 to version 2. Not direct version 1 to version 3.

Thank You.