Save line item property to all items in cart on cart page

Hello

I have a store that currently allows users to pick a date for their orders with the jquery datepicker on the product page, the date gets saved as a line item property when it is added to the cart.


The date picker code has been moved to the cart page, but the same datepicker input is not saving the line item property to the products.

The name=“attributes[Delivery Date]” works, but I need it as a line item.

https://help.shopify.com/en/manual/online-store/themes/os/customize/add-date-picker

How can a line item property be applied to all products in the cart with an input, while on the cart page clicking the checkout button?

Thanks