I am using a plugin called “Product Options and Price Calculation Formulas for WooCommerce – Uni CPO (Premium)” that works fine if I use the default themes like Twenty Nineteen (see screenshot https://prnt.sc/o1u37w). With your theme instead I get the following error (see screenshot https://prnt.sc/o1u4ju).
I contacted the author of the plugin and they told me that the error is caused by the woocommerce outdated file of the SNS Anton theme.
Can you please update the woocommerce files of the theme?
Looking to hear from you as soon as possible
Thank you!