Update Not-a-Match Declaration

Add or edit a not-a-match declaration, indicating that the two referenced persons are separate and distinct individuals and should not be merged together. This operation will fail if there already exists a not-a-match declaration for the person(s).A reason string can be provided indicating why the user believes the two persons to be distinct individuals. The reason is sent as an 'X-Reason' value in the HTTP Headers on the request. This reason can have a maximum length of 2000 characters, and if the reason supplied is more than 2000 characters, the request will fail as an invalid request.