The number (888) 934-6489 is a legitimate Comcast / Xfinity phone number, however, I called them back and they had no notes in my account file that I was called. Their C.S.R. informed me that there have been scammers calling around with a spoofed caller-id using Comcast's number. The CSR said the best way to combat this was to get ask them what the call is regarding and then tell them you will call them back on Comcast's main Customer Service Number. She said Comcast / Xfinity will not call and ask for money or credit card numbers over the phone, if your bill was behind they will advise you to go online and pay your bill or use their automated bill pay over the phone what is not a person asking for your credit card numbers. If the call was legit, Comcast will have notes in your file and will discuss whatever issue they may have called about. The CSR said that Comcast verifies your account through your caller-id phone you are calling from and your service address, so if somebody calls you asking for your account number, account password, WiFi password or internet id / password, it is likely a scammer.