cancel

Stops waiting for loyalty data early - interrupts the local background wait if it is still running, and unblocks any concurrent getResult call that is currently blocked waiting for a result, which then returns a PreTransactionResult whose PreTransactionResult.getLoyaltyData is null. Does not affect the terminal or the payment itself - the wait and the payment are independent. Continue through PreTransactionResult.startTransaction afterwards. A direct Terminal.startTransaction call remains blocked until the pre-transaction is continued or discarded with Terminal.abort.