It likes like Yodel is going into administration. So select another suitable carrier, when the item sells, all you can do is to let your buyers know the valid reasons, for the change in carrier, s you will not be able to change the carrier now on the auction which have bids , or have less than 12 hours to run.
Auctions which have no bids and more than 12 hours to run, just click on the item, top left click on revise, scroll down to Postage section and select another carrier.