Custom Taxonomies disappeared

I have a site that is still in the staging phase, it is using TravelTour – Travel & Tour Booking WordPress theme from Theme Forest.

We needed to change the order of something and they recommended your plugin – worked great – thanks

BUT while updating content in the site last night all of the Taxonomies related to the custom post type “tour” disappeared from the Dashboard and site.

I checked the db and they were all still in there so I started troubleshooting and disabled all the plugins.

I enabled all the core plugins that the theme needs – all worked as it should but when I enabled your plugin the taxonomies disappeared.

I rolled back to a previous version of your plugin and all the site worked ok.

This morning the site had updated tp your latest version again BUT all the taxonomies were visible – the same problem HAD NOT happened again,

Can you shed any light on what could have caused this issue and what I need to do to avoid this in the future?

Thanks