I am using the createOrUpdate endpoint in order to update a customer (or add a customer) and to add that particular customer to a specific list.
My problem is I do not know if that customer already exists and - if so - what contact data they already have.
I know I can do a call before hand - download the contact properties - and update accordingly.
I was wondering if there was an easier/shorter way.
My problem is I am overwriting fields that contain data with blanks. I am sending over empty strings for blank data. If I do something like firstname: null instead of firstname: “” will that leave the existing data alone?
I am trying to not have to rewrite my code. Thanks