If the amount at the time of capture is different from the amount at the time of Pre-auth What happens to the users action?

When the payment amount increases:

If the payment amount increases by 1 yen, permission from the user is required. A notification will be sent to the user to confirm the increased amount. If the user allows the increased payment, the payment is complete.
In addition, the history of changes in the payment amount is displayed on the transaction history screen of the PayPay app.

When the payment amount is reduced:

In the case of reduction, payment will be completed at the time of capturing. No user permission is required.