Product category messed up

Hi I have a site installed with woocommerce 2.0.9. I use the default widget list categories to show the product category. Somehow the parent or current active category is not follow the specific product category.

Example, I have Product A under category X and Y. But when I view the product A in single page, the active category in list category will highlighted category W??

It seen like nothing related with the category W. As I checked the product of A and I can confirmed it is assigned to X and Y.

And I tried with get_the_terms( $post->ID, ‘product_cat’ ) to echo the ID in the product detail page, everytime I refresh it will echo different ID. Not sure what wrong with it.

Please help.

https://www.ads-software.com/extend/plugins/woocommerce/