change property requirement

Change-Id: Iec011026b3b5ba2b48d1d26e3858090e823cc17c
diff --git a/xos/tosca/custom_types/vsm.m4 b/xos/tosca/custom_types/vsm.m4
index f137d5c..c81705f 100644
--- a/xos/tosca/custom_types/vsm.m4
+++ b/xos/tosca/custom_types/vsm.m4
@@ -17,7 +17,7 @@
             xos_base_service_props
             service_message:
                 type: string
-                required: true
+                required: false
             
     tosca.nodes.VSMTenant:
         derived_from: tosca.nodes.Root
@@ -27,4 +27,4 @@
             xos_base_tenant_props
             tenant_message:
                 type: string
-                required: true
\ No newline at end of file
+                required: false
diff --git a/xos/tosca/custom_types/vsm.yaml b/xos/tosca/custom_types/vsm.yaml
index 21f0f67..444c659 100644
--- a/xos/tosca/custom_types/vsm.yaml
+++ b/xos/tosca/custom_types/vsm.yaml
@@ -80,7 +80,7 @@
                 description: Version number of Service.
             service_message:
                 type: string
-                required: true
+                required: false
             
     tosca.nodes.VSMTenant:
         derived_from: tosca.nodes.Root
@@ -97,4 +97,4 @@
                 description: Service specific ID opaque to XOS but meaningful to service
             tenant_message:
                 type: string
-                required: true
\ No newline at end of file
+                required: false