Keeps calling from different numbers

The number that is shown 2026225000 states that it is the US department of Treasury. The Asian that is on the other end of the phone keeps asking for my child. When I asked him why is he calling for a child he mocks me using an Asian accent. The last time he called I pretended to be a male and when he started speaking I told him that I already asked him to please stop calling my phone, he stated f**k you and hung up. The department of treasury should change their number or at least look into this.