code: public static base_response unsign(nitro_service client, dnszone resource) throws Exception {
  		dnszone unsignresource = new dnszone();
  		unsignresource.zonename = resource.zonename;
  		unsignresource.keyname = resource.keyname;
  		return unsignresource.perform_operation(client,"unsign");
  	}
docs: Use this API to unsign dnszone.