Seems like criminals dream up new ways to scam all the time. Here's the latest. Instead of using 900 numbers, today they're using a new approach with area codes like 473, 809, 242, 246 and 649. Once unsuspecting victims pickup, con artists can make money off premium charges. Consumer activists suggest you check the location of an area code on any missed calls to see if you're the target of a con.
Source: http://www.ajc.com/business/consumer-advice/scam-alert-not-answer-calls-texts-from-these-area-codes/G8bu7tNV650m2SuxY07gQO/