POST - https://subscribercrmapi-dev.galapagosconservation.org.uk/api/holdinggroupmember
Updates an existing Holding Group Member.
{ "Id": 1, "HoldingPersonalDetailsId": null, "ContactId": 1234, "GroupId": 1, "DateFrom": "2025-06-23T00:00:00+00:00", "DateTo": null, "OfficeId": 2, "StatusId": 3, "Reason": "", "ToRemove": false}