diff --git a/specification/reservations/resource-manager/Microsoft.Capacity/preview/2018-06-01/reservations.json b/specification/reservations/resource-manager/Microsoft.Capacity/preview/2018-06-01/reservations.json
index c84c093d4fcc..21ac22823e3a 100644
--- a/specification/reservations/resource-manager/Microsoft.Capacity/preview/2018-06-01/reservations.json
+++ b/specification/reservations/resource-manager/Microsoft.Capacity/preview/2018-06-01/reservations.json
@@ -1131,7 +1131,11 @@
                 "On",
                 "Off",
                 "NotSupported"
-            ]
+            ],
+            "x-ms-enum": {
+                "name": "InstanceFlexibility",
+                "modelAsString": true
+            }
         },
         "AppliedScopeType": {
             "type": "string",
@@ -1139,7 +1143,11 @@
             "enum": [
                 "Single",
                 "Shared"
-            ]
+            ],
+            "x-ms-enum": {
+                "name": "AppliedScopeType",
+                "modelAsString": true
+            }
         },
         "AppliedScopes": {
             "type": "array",
@@ -1157,7 +1165,11 @@
                 "VirtualMachines",
                 "SqlDatabases",
                 "SuseLinux"
-            ]
+            ],
+            "x-ms-enum": {
+                "name": "ReservedResourceType",
+                "modelAsString": true
+            }
         }
     },
     "parameters": {