First National Collection Bureau Supposedly I owe 786 dollars for a First premier credit Card that I never used Sparks Nevada

I just received a bill for 786 dollars and 24 cents from First National Collection Bureau INC. Last year I had gotten an unsolicited First Premier Bank Card and was harrassed every day for 3 straight months about a 95 dollar activation fee. I refused to activate the card and cut it up and threw it away. These calls from First Premier Bank continued from October 2013 until February of this year.

Tonight I just received in the mail a bill for the aforementioned 786.24 from First National Collection Bureau INC. I have NO idea how I can owe that much money on a card I never used ONCE and in fact cut up and threw away...