Checkout error after adding gift on cart

We are using Woocommerce Version 5.9.0 we have installed and enabled you plugin with the following settings: Cart Price Rule Minimun Cart Total 1 to offer the gift for any purchase and added on single gift product. When the user click on add your gift, the gift is added to the cart. When the user click on proceed to checkout, he is getting the following error: “There are some issues with the items in your cart. Please go back to the cart page and resolve these issues before checking out.” Once the user remove the gift item fron the cart, he can proceed to checkout normally without errors. Please advise

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