Fatal error after installing version 3.6.9

Hello,,, I installed the last version of plugin however in WOO log I got this error, and also in WP dashboard all saved products unselect categories that was selected before some product still connect with main category but lost connection to sub or sub-sub category!

Here is the error message written by Woo Logs

CRITICAL Uncaught Error: Call to a member function is_taxonomy() on string in /home/mataaaco/public_html/wp-content/plugins/mstore-api/functions/index.php:466

The page I need help with: [log in to see the link]