We booked a holiday to the U.S. It involved 2 transfers there and 2 back. We booked through klm (some flights are operated by delta on behalf of klm), I got a message saying to request a voucher or refund with no fee to do so. I did that and got an id code through and thought that covered all the flights and that was it. I've been receiving emails telling me each flight that's been cancelled and to re book, refund, voucher. I've messaged the airlines as to whether this means I've got to apply for each flight separately but no reply. I've never had to deal with this scenario. The vouchers are valid with klm, delta, and air France. I'm aware that they'll be inundated and trying to work through a deluge of work so I'm not anticipating a reply soon. Does anyone know if I have to apply for every flight ?