Hello,
Thank you very much for choosing our theme and for contacting us.
I cannot enter your site and check. The access is not workable. https://prnt.sc/10d7l7v
Please make the full backup of your site as well as the Theme settings export and check the issue on the Storefront theme to detect if our theme causes the problem.
If you see the same on the Storefront, it means that you:
a) Have configured the variable product not correctly, please check this instruction: https://docs.woocommerce.com/document/variable-product/ Make sure all the variations have their individual prices and stock.
b) If you have configured everything correctly, deactivate all the plugins not related to the theme and switch the parent theme, check the issue, If the problem has gone, activate the plugins one by one, checking the issue to detect which one causes the problem.
Hope you will find the reason, in any case, contact us if you need further help.
Best Regards