diff --git a/src/auth/AuthController.ts b/src/auth/AuthController.ts
index 52bf6f1..6cad640 100644
--- a/src/auth/AuthController.ts
+++ b/src/auth/AuthController.ts
@@ -6,6 +6,7 @@ import ModelFactory from "../db/ModelFactory";
 import User from "./models/User";
 import UserPasswordComponent from "./password/UserPasswordComponent";
 import UserNameComponent from "./models/UserNameComponent";
+import {UnknownRelationValidationError} from "../db/Validator";
 
 export default class AuthController extends Controller {
     public getRoutesPrefix(): string {
@@ -103,10 +104,9 @@ export default class AuthController extends Controller {
     }
 
     protected async redirectToRegistration(req: Request, res: Response, identifier: string): Promise<void> {
-        req.flash('register_identifier', identifier);
-        req.flash('info', `User with identifier "${identifier}" not found.`);
-        res.redirect(Controller.route('auth', undefined, {
-            redirect_uri: req.query.redirect_uri?.toString() || undefined,
-        }));
+        const error = new UnknownRelationValidationError(User.table, 'identifier');
+        error.thingName = 'identifier';
+        error.value = identifier;
+        throw error;
     }
 }