ERROR [HY000] [Microsoft][QuickBooks] (60) API Connection Failed (Unauthorized Access). HTTP Response code: 403 Activity ID: cefcc263-c524-4307-aa3b-df2435988819.

Let me route you to our Developer's page, @agarwal-shruti4-

We have a different Community for app developers, where you can interact with other users and our Support team regarding APIs. They can check to fix the error message you're getting and help you resolve them.

 I'll walk you through the steps to reach them.

1. Go to this link and log in using your Intuit account: https://help.developer.intuit.com/s.
2. Select QuickBooks Online under the What do you need help with? section.
3. Click Ask a Question and enter the details of your concern.
4. Click Ask.

Just like in the Community, your post will be displayed in the form and anyone with knowledge or idea about will join the conversation.

You can also check out our tutorials page to see more details about other features in your QuickBooks Online (QBO) account. 

If there's anything else that I can help you with, please let me know in the comment section down below. I'll be always around ready to help. Have a wonderful day, @agarwal-shruti4-