Payment Gateway Integration

Looking for someone who can help us understand the payment flow for https://developer.mobilepay.dk/product
Just a postman collection with the flow should be good for us.
Refer to POS flow!
We are looking forward to:
- Scan a QR code
- Capture an amount
- After the user uses the service, we deduct the payment
- Refund the rest
Please add "MP" before starting the bid