Your post is what is a bunch of hooey. You do NOT have to update your DNC registration - ever. Didn't you read the info on the site when you first registered your number?
https://www.donotcall.gov/register/reg.aspx
Legitimate telemarketers do pay attention to it. If not on the DNC list, you'd be getting even more calls.
It was Heather from "Card Services!!!" How are these people still operating? Didn't the FTC shut them down recently? I am on the Do Not Call List, and they called a Mobile Number! I was in an important meeting too, and my ring tone is "Trololo" so that was funny for all, but a huge interruption. Can I sue them for embarrassment??? LOL