Why do I get the "IoStoreOnDemand.ChunkMissingError" error when trying to equip certain cosmetic items in Fortnite?

We're aware that some players are getting the "Item could not be downloaded. Please try again later. Error IoStoreOnDemand.ChunkMissingError” error when trying to equip certain cosmetic items in the Fortnite Locker, and our team is currently investigating this further.