Either use FTPiiu to manually delete the files from the usb or reformat the stick and redownload the game. It's a fool's errand anyway because you'll probably run into the same issue.
They made an accout just to ask that question. If only there's some kind of search engine on the internet. I could make one, I think I'll call it Ask Jeeves.
btw i feel this a good time to remind you guys that sea of thieves was made by rare, who also made DKC1-3 and DK64, alongside banjo kazooie and conker's bad fur day