I got curious to see if I could sell my 6s plus. so i put up an ad. now since i turned down their offer they're threatening to blacklist my phone with at&t through the imei. i'm sure they're just mad they couldn't try to get it for a cheap price and threatened this. I'm sure theres no way they could do that since they would need access to my account, know my social security, and more info about me to try to do something with just that number. just wondering. wont do that again lol --- Post Merged, Jul 13, 2016 --- quick update. just got off the phone with at&t and they said theres no way for them to do that any other way other than through the carrier. and they would need all my personal info.