Yes, we have this same issue too. Looks like when you update the plugin it will delete all your post type plugin entries. Then you add them again and they won’t save. If you navigate away from the post type entry page within the plugin and navigate back, the plugins are deleted.
I had to revert back to the previous version. I had to add the plugins to disable back in my post type product. However, they do save now on the older version of 9.1.2.
Maybe you can add a way to save & export our settings within the plugin. This way if something goes wrong we can quickly add back our settings for this plugin. Seems that your upgrades are clearing the database entries for post type product and not allowing to save our settings?
I learned from previous updates to backup the plugin prior to update.
We love the plugin and appreciate your hard work. You should really charge for this plugin as it is a must and brilliant.
Kind Regards