Add the identification models introduced in version 20260901 to an agreement created without them: the initiating client and the debtor's registered payment account. Identification can only be added, never changed, and must match the details already on the agreement. Each identification can be added in a separate request. The debtor payment account must belong to the agreement's initiating client; adding one to an agreement with no initiating client identifies you as the initiator. Supply initiator.client_id for any agreement initiated on behalf of a sub-client; without it the agreement is identified as initiated by you.