adding previous donation balance

Hello,

I redirect the add to cart button to a custom page where the donate shortcode is placed instead of redirecting to cart or checkout. I also disabled the donate button on the cart and checkout page. I only want users to donate through the shortcode page.

The problem now is when my cart is empty and I click on the add to cart button of the donation product I am now redirected to the donate page where the user indicates the amount for donation, but I noticed that my cart already contains the donation product with a previous donation balance instead of a zero balance even when i’m yet to click the (add donation) button on the custom page.

This is the plugin I use to redirect the add to cart button to a custom page instead of cart or checkout page https://www.ads-software.com/plugins/woocommerce-add-to-cart-custom-redirect/

Thanks