You can complete the payment for an amount that is lower than the pre-authorised amount.
The platform also allows you to complete a payment for a value that is larger than the pre-authorised amount. However, we do not recommend this approach as we cannot guarantee that the issuer will accept a higher completion amount. Instead, we recommend that you create another payment for the additional amount. This new payment will need to be authorised separately/again by the cardholder.
You may only perform a single completion on an authorise-only payment. Any remaining balance on the authorisation will be released to the cardholder. You should also ensure you complete the payment within the applicable timeframe, otherwise the issuer may have released the hold on the account.