Edditing formula

[#1]

Having hard time figuring out this formula below works on Qlik Sense.

Is there anyone who knows how to make it works?

if(isnull([ship_dt]) = false and isnull([p_return_dt])=false) then

[수주금액]*(-1)

else if (isnull([ship_dt])=false and isnull([p_return_dt])=true) then

[수주금액]

else

0

end

[Gysbert_Wassenaar]

See your other discussion with the same question: way to work this formula on Qlik Sense‌

Please try to avoid posting the same question twice.