These people call you because you somehow thought you were getting in contact with the U.S. Immigration center and they will charge you to fill out the applications needed for citizenship or what ever the case maybe. after you fill out the pre app and it gets to the credit card part and you leave the website they will call your number asking you if you need help and want to charge you for the application and it doesn't include the real application to the real Immigration offices.
I just got a phone call from this number, and a foreing lady was asking me about an Immigration form I never filled it out in my life. She said she worked for Immigration Office. It is so fishy she knew my name and my phone number, but that happened after I visited the passport office to get my baby's passport. Be careful out there with this people who are trying to help you fill out a form, and will steal your personal information. Don't give your social or any other personal information.