diff --git a/core/service.go b/core/service.go
index 61f9c56..e20a769 100644
--- a/core/service.go
+++ b/core/service.go
@@ -237,7 +237,7 @@ func (sh *serviceDescription) prepare(mg *Maingate) error {
 					div.Maintenance.link = div.Maintenance.Notice
 				} else {
 					var fd FileDocumentDesc
-					if err := sh.mongoClient.FindOneAs(CollectionFile, bson.M{
+					if err := mg.mongoClient.FindOneAs(CollectionFile, bson.M{
 						"key": div.Maintenance.Notice,
 					}, &fd, options.FindOne().SetProjection(bson.M{"link": 1})); err != nil {
 						logger.Println(err)