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Your main contact for support in Opaali API related issues is the Contact Us form in Opaali Portal. If you already have an Opaali user account you should log in to the portal before filling in the Contact form, this way your account details are pre-filled on the form. You will get a reply faster if all the details are included. (You can use the form also if you don't yet have an Opaali user account.)But before that, you should check out the official documentation at the Opaali Portal.