Hi there!
I certainly see the issue with OH addresses, very strange. I can’t replicate this on my site.
Usually issues like this may be caused by either a conflict with your theme or with another WordPress plugin. We address this type of problem by asking you to temporarily disable all plugins except for WooCommerce (and the extension), and switch back to a default WordPress theme like Twenty Seventeen or Storefront -https://www.woothemes.com/storefront/.?You can just do a Live Preview under Appearance with one of these themes and browse to that page and test. If it works there, then it’s a theme issue.
If that resolves the issue, then slowly re-enable the theme first, and then plugins one at a time until you find the one that’s causing the conflict.
If you don’t want to do these tests on your live site, many hosts provide a staging service – they clone your site onto a “stage” where you can do testing without affecting the live version. You can ask your host about this. If they don’t give you a staging site, we recommend using WP Staging – https://www.ads-software.com/plugins/wp-staging/ or Duplicator https://www.ads-software.com/plugins/duplicator/
Let us know if this works for you, thanks!
