diff --git a/animeverse/animeverse.js b/animeverse/animeverse.js
index 55c78d4..ff4746b 100644
--- a/animeverse/animeverse.js
+++ b/animeverse/animeverse.js
@@ -73,7 +73,14 @@ async function getAuthKeyAndCookie() {
     if (!sessionData.clientAuthKey) {
         throw new Error("Session bootstrap failed: " + sessionText);
     }
-    const setCookie = sessionRes.headers.get('set-cookie');
+    let setCookie = null;
+    if (sessionRes.headers) {
+        if (typeof sessionRes.headers.get === 'function') {
+            setCookie = sessionRes.headers.get('set-cookie');
+        } else {
+            setCookie = sessionRes.headers['set-cookie'] || sessionRes.headers['Set-Cookie'];
+        }
+    }
     cachedAuthKey = sessionData.clientAuthKey;
     cachedAuthExpires = sessionData.expiresAt - 10;
     cachedCookie = setCookie ? setCookie.split(';')[0] : null;