Hello, 

I am having an issue with CRM and Books synchronization. I am writing it here because I tried to reach you over the online chat, but I always got no helpful solution, so I thought to make a topic here to follow up here correctly.

When the sync triggered for the first time, all contact was transferred to CRM from Books. Later on, the Books customers started to get duplicated by CRM.

I did all the configurations as in the attachments. If I delete the duplicated contact in Books, as soon as it gets updated in CRM, it gets duplicated again in Books.

Thanks