HTTPS Security do you see the safe lock in your browser on your site? Does the address start with https:// ? If not, this is another area to check right away.
You may not realize it, but the security of your site can affect voice search just like it can text search. If people (including robots) go to your website and it does not appear secure, they are going to leave. Your shopping cart itself is secure, but you need to ensure your entire site is secure as well.
https://whynopadlock.com is a helpful spot to check your site