I had temporarily set my cell phone to allow unknown numbers to ring, as I was waiting for a possible callback from a hiring manager. Instead I got a call from "AT&T" (my wireless provider) telling me I qualified for a steep discount on my wireless service. He seemed to be looking at my account, asked about the second phone number (my Apple Watch has cellular so has its own number). [edit, this got lost at some point during writing this] I then got a verification text from AT&T, he just needed that number to set up the discount. That's when I knew for sure that he was trying to hijack my phone number to his device. I already set up a sim/account lock so nothing's moving. I just hung up. Here are my questions: How did they see the information like my watch's cellular number they verified on my account? Why steal a phone number unless they already knew what bank accounts I have? Would they already have that information or just use my phone number to gather the info and then raid them? Thanks much in advance.