Posta in Arrivo - ilar

Hi, I need to validate your translation and I'm a little puzzled by the following sentences.
不是: 为什么?，回答
是的: 写

Could you perhaps explain what the text means? My guess is, it means:
If not, why? Please state reason.
If yes, please indicate your agreement.

Am I correct?

Are you speaking chinese fluently or are you using a dictionnayr/automatic tool ?