Called cell left no message

WARNING--BEWARE!! These callers are   B I G   credit card criminals, known as the card service scammers! Under NO circumstances, give these lowlifes your credit card number, or you will regret it forever!

How can I report that I received a call from this number? Who shall I contact? A robo voice asked if I want to delete this number from calling again. It said to press 1 to take it off the calling list and so I did. Was this a mistake? Please help me.

Yes, it WAS a mistake to press any number. By answering, and especially by pressing numbers, you can expect to receive MORE calls from these, AND other scammers. Don't answer calls from numbers you are not familiar with! As far as reporting the callers is concerned, if you are registered on the State or Federal do not call registries, you may report them as violators, but the value of doing so is questionable, as the scammers use spoofed numbers. If you did not give them your credit card number, they can do you no harm, they are simply pests.

My state attorney generals office/do not call list says to never answer them or call them back.  They call my cell and on the reject list they went.  I bought a 1500 number blocker device for my home phone.  Well over 40 numbers blocked just in the last 2 months. Many of them daily repeat offenders.  The do not call programs even at the State level are pretty much worthless.  My state won't even take a report unless I answer and talk to them. Not on your life will I do that.