diff --git a/services/preview/resources/mgmt/2018-03-01-preview/managementgroups/managementgroups.go b/services/preview/resources/mgmt/2018-03-01-preview/managementgroups/managementgroups.go
index 57a4e7e71afc..1fbbbbcb75f9 100644
--- a/services/preview/resources/mgmt/2018-03-01-preview/managementgroups/managementgroups.go
+++ b/services/preview/resources/mgmt/2018-03-01-preview/managementgroups/managementgroups.go
@@ -366,7 +366,7 @@ func (client Client) GetDescendantsPreparer(ctx context.Context, groupID string,
 	}
 
 	preparer := autorest.CreatePreparer(
-		autorest.AsPost(),
+		autorest.AsGet(),
 		autorest.WithBaseURL(client.BaseURI),
 		autorest.WithPathParameters("/providers/Microsoft.Management/managementGroups/{groupId}/descendants", pathParameters),
 		autorest.WithQueryParameters(queryParameters))
diff --git a/services/preview/resources/mgmt/2019-11-01/managementgroups/managementgroups.go b/services/preview/resources/mgmt/2019-11-01/managementgroups/managementgroups.go
index 627a1a0ff13a..357f80eaa8a1 100644
--- a/services/preview/resources/mgmt/2019-11-01/managementgroups/managementgroups.go
+++ b/services/preview/resources/mgmt/2019-11-01/managementgroups/managementgroups.go
@@ -366,7 +366,7 @@ func (client Client) GetDescendantsPreparer(ctx context.Context, groupID string,
 	}
 
 	preparer := autorest.CreatePreparer(
-		autorest.AsPost(),
+		autorest.AsGet(),
 		autorest.WithBaseURL(client.BaseURI),
 		autorest.WithPathParameters("/providers/Microsoft.Management/managementGroups/{groupId}/descendants", pathParameters),
 		autorest.WithQueryParameters(queryParameters))