American Cash Awards — prize claim (us$ 10.5 m. and a 2017 mercedes benz) notification

I was notified by Mr Robert James: the financial Advisor and Manager as he introduced himself to me. That I was first winner of $10.5 m(ten million five hundred thousand dollars) and a 2017 mercedes Benz car. But he never gave his official contacts only asked me whether am willing to claim my won prizes. Of which I said yes and requested for his official contacts and how to claim and requested him to send me a letter of invitation to enable enter the USA to claim my prizes. But no response. Was it a scam or really prizes.
Can you kindly clarify to me?
thanks
Erastus Nyamera Masira- fb- masira erastus nyamera.
Tel. +[protected] email. [protected]@hotmail.Com and [protected]@live.Com