Why wouldn't "Gör du ser min kalender." be excepted?
Because the construction with "to do" as an auxuliary verb isn't something Swedish does.
Whay was "Ser ni min kalendar" correct?
two of these would work here. Du and ni. Thy system just doesnt recognise that they both translate to you.
but actually i take that back i just noticed they used mitt and min in another one so actually it is right there is only one correct answer. You just have to pay attention to weather or not its an en or an ett word.