It says a required field was left blank but it does not apply to me (If a gift...)

[aperezal]

Hello, 

I already paid for my ufile to file my 2021 taxes, but when I am ready to file it says the calculations cannot be done because 2 required fields were left blank. However, the required fields do not aply to us. This is in the capital gains section, because we sold our townhouse in 2021. This was not a gift to a charity, Canada or the province. Should I enter $0, even when it was not a gift? I tried that and it still does not work. Please, see the screenshot attached. 

Thanks,

Ana.