Regarding the issue you mentioned (“checkout options disappear from settings”), based on the behavior you’re describing, this is most likely caused by a conflict with another plugin or with the active theme on your site.
To help me investigate this further, could you please provide the following details:
- Your WordPress and WooCommerce versions
- Whether you are using the Classic Checkout or WooCommerce Blocks Checkout
- Whether HPOS (High-Performance Order Storage) is enabled
- Please also try switching temporarily to a default theme (for example Storefront) and disabling all plugins except WooCommerce and IRIS, to check whether the issue still occurs
With this information, I’ll be able to investigate further and advise you on the next steps.