PJ,
In this instance, the original CS01 ought to have included this information - as such the most straightforward way to resolve this would be to “second file” the relevant part of the confirmation statement. You should do this by filing part 5 of the confirmation statement alongside form RP04 – you should not send in another confirmation statement itself, just the relevant part that contains the information that they are trying to correct.
Please note that the “second filing” procedure can be only be carried out on paper.
SDN