Hi,
There were no code changes in the last Simple Sales Tax update. We strictly bumped the supported versions of WooCommerce and WordPress in the plugin headers. In addition, this error didn’t show up in our automated or manual testing and I can’t reproduce it now. It is extremely unlikely that whatever you are experiencing is directly related to SST or any recent updates to it.
It’s hard to tell with just the truncated error message you provided, but it looks like there’s some code on your site – perhaps a plugin you updated recently, perhaps a custom code snippet in your theme – that is unsetting the ‘data’ property on the cart items in the WooCommerce cart shipping packages. This property is strictly required by SST and if this theory is correct you’re going to have to find the offending plugin/theme code and either disable or update it to correct the issue. One way to go about this would be to install a standard core WP theme (like Twenty Twenty Two) and deactivate all plugins except for WooCommerce and SST to see if the problem goes away. If it does, then you can reactivate plugins and your theme one by one until the issue reappears to identify the culprit.
In the meantime if you send a copy of your WooCommerce > Status report and the full text of the error message to [email protected] and I can do a little more digging to try to identify the conflicting code and definitively confirm that the problem was not caused by a recent SST update.
– Brett
