If the v2 order was intent:'authorize'
and you 'COMPLETED' it to get back an authorization object, you can void the authorization using the v2/payments API.
If, however, the order was merely 'CREATED' or 'APPROVED', there is no way to cancel or void it. Simply have your system forget about it.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…