diff --git a/msc/USSD_Helpers.ttcn b/msc/USSD_Helpers.ttcn
index 6a71681..5dd4bb1 100644
--- a/msc/USSD_Helpers.ttcn
+++ b/msc/USSD_Helpers.ttcn
@@ -60,4 +60,19 @@
 	return enc_SS_FacilityInformation(facility_ie);
 }
 
+function f_USSD_FACILITY_IE_RETURN_ERROR(
+	integer invoke_id := 1,
+	SS_Err_Code err_code := SS_ERR_CODE_UNEXPECTED_DATA_VALUE
+) return octetstring {
+	var SS_FacilityInformation facility_ie;
+
+	/* Encode Facility IE */
+	facility_ie := valueof(ts_SS_FACILITY_RETURN_ERROR(
+		invoke_id := invoke_id,
+		err_code := err_code
+	));
+
+	return enc_SS_FacilityInformation(facility_ie);
+}
+
 }