Conflict with WooCommerce

Hi,

I have recently updated wordpress to 5.2.1 and woocommerce to 3.6.4. After the update Hyyan WooCommerce Polylang started to cause problems.
1. When it is active I cannot publish the new product or add translation.
2. Always error is displayed after any update of existing product
3. When I am trying to update stock in simple edit. Update fails and product is shown as out of stock.
Any suggestions for non-it professional?

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