Spam though Phone

I got the same thing u get in junk mail on my phone. The problem is the internet and know phone numbers are give or sold to these people. I went online thought at&t service and went to ( jobs.com ) looking for a job. In process u give ur phone number in hope of recieving a call from and employer wanting to hire. Since then I have gotten hundreds of calls from schools that I didn't want and even answered a question saying I didn't want to farther my education. NO calls about a job but tons of junk in email and phone. SAD!!!!!