Fix conversation messages

Change-Id: I999839176bf523f1968dada3e3ebd8703f08656f
diff --git a/client/src/utils/auth.ts b/client/src/utils/auth.ts
index 822771c..73b5522 100644
--- a/client/src/utils/auth.ts
+++ b/client/src/utils/auth.ts
@@ -80,9 +80,8 @@
   }
 }
 
-export function getAccessToken(): string {
-  const accessToken: string | null = localStorage.getItem('accessToken');
-  return accessToken ?? '';
+export function getAccessToken(): string | undefined {
+  return localStorage.getItem('accessToken') ?? undefined;
 }
 
 export function setAccessToken(accessToken: string): void {