Re: I can't copy existing contact on new contact list.
I had to take some time to look into this library as it is built for an older and now deprecated verison of our API. After investigation, I found that the way that UpdateContact is implemented, it will only work if the Contact object is created by using the searchContactsByEmail method. If you do not get the contact details this way, then a required property of the contact object is not set, causing the UpdateContact method to fail.
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