Remove item with $product_id - Woocommerce

Question

Made a function where the customer get a product added to the cart when they reach a specific amount.

Example of when customer reaches level 3 and get the

Answer 1

I think you're using remove_cart_item incorrectly. If you go through the documentation, you will find that it accepts cart_item_key as parameter (as wisdmLabs mentioned in comment).

You are using it like so:

WC()->cart->remove_cart_item($product_3);

Try this instead:

WC()->cart->remove_cart_item($cart_item_key);

After updating that line, I think you will able to remove product.