My Checkbox on main-cart-items.liquid not working

[LBook11]

it always says there was an error everytime this is clicked, tried to push through with the order, and no additional comments were found on the order. It works before and it shows "additional comments: Shopee Checkout" on the order. I didnt know what i did wrong and not it doesnt work, same happens when i put a dropdown box, i just removed it from the code.

can anyone help me? thank you so much!

here is my website www.lostbookph.com