Free shipping Free version ?

Hi,
I have been using the standard wordpress shipping in woocommerce where i have a free shipping within certain zipcodes and other zipcodes must pay a freight based on the weight from your plugin.

But i can’t see how i can show my customers that are able to have have free freight based on their zipcode without also they have to see a field with the freigt from your plugin,
is it not possible just to show free freight without also the charge for shipping if they was not able to have free freight?
So hide the freigt field IF a customer is able to get free freight based on their zipcode ?
https://ibb.co/4pfRRHb