To answer your question, you are not in the right place for an IAT/ICA query because the IAT/ICA number is not directly related to the Visa Developer Portal, therefore, I will not be able to comment directly on how you will get the IAT/ICA number. Please contact the person asking you to provide IAT/ICA number for the significance of IAT/ICA.
However, I can help to provide you with further assistance, if you send an email and reference this community forum post to firstname.lastname@example.org.
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