diff --git a/backend/database.mv.db b/backend/database.mv.db
index b8c3ac5..ce9acb8 100644
Binary files a/backend/database.mv.db and b/backend/database.mv.db differ
diff --git a/backend/src/main/java/com/example/backend/anwprj/controller/UserController.java b/backend/src/main/java/com/example/backend/anwprj/controller/UserController.java
index 1bf128e..1647821 100644
--- a/backend/src/main/java/com/example/backend/anwprj/controller/UserController.java
+++ b/backend/src/main/java/com/example/backend/anwprj/controller/UserController.java
@@ -51,6 +51,7 @@ public class UserController {
             }
         }
 
+        mail = mail.toLowerCase();
         String sessionID = UserSessionIDHandler.addUser(mail, password);
 
         return new ResponseEntity<>(sessionID, HttpStatus.OK);