I keep getting this error message

https://preview.redd.it/0evd022kelyg1.jpg?width=3024&format=pjpg&auto=webp&s=31119f001df7f4ea2cf0e5cfe08bd289c367b3da

So I bought this switch pre modded. I was given a video to follow, by hyper 998 called how to use CFW on sysnand and not get banned. After I followed what that video said I got this message. I went through some trouble shooting with who I bought it from and we couldn't figure it out. I don't know how to fix it.