Lease companies can sometimes be very badly informed of the law regarding postal PCNs.
I suggest you first check with them to make sure they haven't paid it at the discounted rate, because if they have it is game over, because then, the council will not send out a PCN to you. Secondly, if they have merely reported your name and address, ask them when they received advice from the council that their PCN had been cancelled. The council have 28 days to serve the second PCN from date of cancellation of the first one.