diff --git a/CDT-notification.xsd b/CDT-notification.xsd
index 49058913e5afbcbbaf7a6900f0fb64045eafaffd..b7e6c18b0a739459a40bc43f09f533d5910129d3 100644
--- a/CDT-notification.xsd
+++ b/CDT-notification.xsd
@@ -74,8 +74,8 @@ oneM2M EXPRESSLY ADVISES ANY AND ALL USE OF OR RELIANCE UPON THIS INFORMATION PR
                         </xs:element>   
                     <xs:element name="AERegistrationPointChange" type="xs:boolean" minOccurs="0"/>
                     <xs:element name="AEReferenceIDChange" type="xs:boolean" minOccurs="0"/>
-                    <xs:element name="trackingID1" type="m2m:ID" minOccurs="1"/>
-                    <xs:element name="trackingID2" type="m2m:ID" minOccurs="1"/>
+                    <xs:element name="trackingID1" type="m2m:ID" minOccurs="0"/>
+                    <xs:element name="trackingID2" type="m2m:ID" minOccurs="0"/>
                     
                 </xs:sequence>
         </xs:complexType>