No events after updating from 2.2.2

Hi I have been trying to update a old blog im working on for a charity which they haven’t updated in ages and when i try and update to the new latest version of this events plugin they all disappear, after doing some research it says there is a update tables button in the help section, although i could find this when clicked it didn’t work.

Can anyone help as im a bit lost now as to what to do? I have duplicated the site onto my test server which is where i was running the upgrade.

thanks

https://wordpress.org/plugins/events-manager/