diff --git a/apps/hub/app/(app)/admin/event/_components/Form.tsx b/apps/hub/app/(app)/admin/event/_components/Form.tsx
index eab98338..f765118c 100644
--- a/apps/hub/app/(app)/admin/event/_components/Form.tsx
+++ b/apps/hub/app/(app)/admin/event/_components/Form.tsx
@@ -256,7 +256,7 @@ export const Form = ({ event }: { event?: Event }) => {
 										<Calendar className="h-5 w-5" /> Teilnehmer
 									</h2>
 								}
-								searchFields={["User.firstname", "User.lastname"]}
+								searchFields={["User.firstname", "User.lastname", "User.publicId"]}
 								ref={appointmentsTableRef}
 								prismaModel={"participant"}
 								filter={{
diff --git a/apps/hub/app/(auth)/passwort-reset/action.ts b/apps/hub/app/(auth)/passwort-reset/action.ts
index 2ed3775d..a2ca9337 100644
--- a/apps/hub/app/(auth)/passwort-reset/action.ts
+++ b/apps/hub/app/(auth)/passwort-reset/action.ts
@@ -13,7 +13,7 @@ export const resetPassword = async (email: string) => {
 				email,
 			},
 		});
-		const oldUser = (OLD_USER as OldUser[]).find((u) => u.email === email);
+		const oldUser = (OLD_USER as OldUser[]).find((u) => u.email.toLowerCase() === email.toLowerCase());
 		if (!user) {
 			if (oldUser) {
 				user = await createNewUserFromOld(oldUser);
diff --git a/apps/hub/app/(auth)/register/action.ts b/apps/hub/app/(auth)/register/action.ts
index a15bf2df..0cbe1a43 100644
--- a/apps/hub/app/(auth)/register/action.ts
+++ b/apps/hub/app/(auth)/register/action.ts
@@ -29,7 +29,7 @@ export const register = async ({ password, ...user }: Omit<Prisma.UserCreateInpu
 		},
 	});
 
-	const existingOldUser = (OLD_USER as OldUser[]).find((u) => u.email === user.email);
+	const existingOldUser = (OLD_USER as OldUser[]).find((u) => u.email.toLocaleLowerCase() === user.email.toLocaleLowerCase());
 
 	if (existingUser) {
 		return {
diff --git a/apps/hub/app/api/auth/[...nextauth]/auth.ts b/apps/hub/app/api/auth/[...nextauth]/auth.ts
index e6250f80..acf2930c 100644
--- a/apps/hub/app/api/auth/[...nextauth]/auth.ts
+++ b/apps/hub/app/api/auth/[...nextauth]/auth.ts
@@ -20,7 +20,7 @@ export const options: AuthOptions = {
 					const user = await prisma.user.findFirst({
 						where: { email: credentials.email },
 					});
-					const v1User = (oldUser as OldUser[]).find((u) => u.email === credentials.email);
+					const v1User = (oldUser as OldUser[]).find((u) => u.email.toLowerCase() === credentials.email.toLowerCase());
 					if (!user && v1User) {
 						if (bcrypt.compareSync(credentials.password, v1User.password)) {
 							const newUser = await createNewUserFromOld(v1User);