## Integrated Pre-Authorisation — Managing & Updating ## Pre-Auth Completion Reference When a pre-auth is successfully opened, TTA returns a Pre-Auth Completion Reference. This reference must be stored by the POS and used for all future actions on the pre-auth. ## Increasing a Pre-Authorisation ### Event-Based Method ```c# IPreAuthCompletionResult IncreasePreAuth( string completionReference, int amount, string? merchantID = null, string? terminalID = null, string? transactionId = null ) ``` ### Task-Based Method ```c# Task IncreasePreAuthAsync( string completionReference, int amount, string? merchantID = null, string? terminalID = null, string? transactionId = null ) ``` ### Parameters | Parameter | Description | | --- | --- | | completionReference | Identifier from the original pre-auth | | amount | Incremental amount (in cents) | | merchantID | Optional override | | terminalID | Optional override | | transactionId | Optional override |