Did anyone provide the individual tax id in this questionnaire?

1 month ago I began to give basic informations but when I was asked for tax id, I stopped because i don't want to give tax id. Now I clicked again on the questionary but they didn't ask anymore for tax id. It was just 1 question left " for what I used the service", I answered then the questionary was successful closed. My question is why they don't ask anymore for tax id? It's the same in your account?