PAYPAL Express sometimes NOT Adding Shipping cost during PayPal login

[HeyIts007]

ZenCart v 1.3.9h upgraded from 1.3.9g

PAYPAL Express sometimes NOT Adding Shipping cost to final price. Any ideas why ?

For example if I add a product to the cart and then select the "Checkout with PayPal" button it does not add the freight cost.

However if I first use the "Go to Checkout" option within ZenCart and then go back and Checkout with PayPal, it adds the freight cost.

This is non consistent though. Sometimes it works straight up and sometimes I need to go to checkout in ZenCart first to get the shipping cost registered.

This seems to be more of a problem when the user is NOT logged in, but the problem still sometimes happens even when logged in.

Very odd and concerning as it means customers can sometimes order products and not pay the shipping charge.

ZenCart v 1.3.9h upgraded from 1.3.9g