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While trying to register a marketplace domain as documented on (https://developer.apple.com/documentation/appstoreconnectapi/add_a_marketplace_domain) I'm getting the following error: {'errors': [{'id': '911f9861-23b3-42a2-80d2-a46bc7218246', 'status': '409', 'code': 'ENTITY_ERROR.ATTRIBUTE.INVALID', 'title': 'The provided entity includes an attribute with an invalid value', 'detail': 'Provided domain is invalid.', 'source': {'pointer': '/data/attributes/domain'}}]} I've tried multiple forms of writing the same domain and keep getting the same error. Wondering if there are any special rules for the domain format that I'm unaware of.