Zapier integration creates duplicate contacts

Zapier integration creates duplicate contacts

Hi,

I am using zapier to (try to) update or create a contact in Zoho books, every time that contact is updated in Shopify.

I have only the "Create contact" action, which, sadly, only creates new contacts but never updates existing ones.

How can i simply update contacts?

(even if it's a complex trick, i can take it!)