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One option is to first use xID to authenticate the user without the need for Additional Information. Then, you can request Additional Information at a later time when it is necessary in the workflow, for instance during a checkout prosess. In this use case the the id_token_hint option option shold be used for the second request,.
Another option is to postpone the authentication of the user until you know it is necessary to request Additional Information. In this case only one transaction will be sufficient.
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