Need to save metafields in the customer object in the checkout ui api

[JtorresLC]

Im trying to save some Metafields to the Customer object with the checkout extensibility.

We need to save these metafilelds because are additional customer. So the final goal is the customer can save this data, and in the future, can preload this data to the checkout and not have to fill these fields again.

Hope there is a way to this!.

Thanks for reading.