UPI Payment Integration with Auto-Update -- 2

I need a UPI payment integration example where the page automatically receives response upon payment completion.

Current Attempt:
- We have a page where entering UPI displays a generated QR code.
- After scanning the QR code, we need a way to confirm that payment is done.
We we tried creating: https://lokalneeds.in/new/Shoppayemnt.html

Requirements:
- Automatic update upon payment completion
- Display error message if payment fails

Ideal Skills and Experience:
- Experience with UPI payment integration
- Proficient in QR code generation
- Web development skills to implement page logic and updates
- Familiarity with frontend frameworks for a smooth user experience

Our website is in PHP. We have Payu payment gateway.