KeyError: key Float64 not found

New to Julia
1

I am very new and I think my Julia works well before but after I restart the computer, I get this error

Screen Shot 2020-11-26 at 11.46.08 AM
Screen Shot 2020-11-26 at 11.46.08 AM2042×402 67 KB

how can I fix this, thank you for any help.