won a lottery

To DR. James
 sir
  I have received a message on my mobile No:+919706216844 that my mobile no. has won the sum of (GBP)700000.00 pound on this year of coco-cola promo.
As i am not aware of the claiming procedure of this subject matter so kindly help me to retrieve my reward.(wishing that it's not a joke).
                                                      claimant:
                                                       pappu chakraborty
E-mail id:
                                                      mrpappu.chakraborty@gmail.com