diff --git a/src/parentClient.ts b/src/parentClient.ts
index 73a4e15..eaf9520 100644
--- a/src/parentClient.ts
+++ b/src/parentClient.ts
@@ -58,7 +58,7 @@ export class ClasschartsParentClient extends ClasschartsClient {
 
     this.authCookies = cookies;
     // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    let sessionID: any = decodeURI(cookies[2])
+    let sessionID: any = decodeURI(cookies[1])
       .replace(/%3A/g, ":")
       .replace(/%2C/g, ",");
     sessionID = JSON.parse(