Amazon India — empty box without product delivered

Address:	Dakshina Kannada, Karnataka, 575002
Website:	www.amazon.in

I had ordered for a sonata analog multicolour dial women's watch on 12 november sold by cloudtail india private limited bengaluru, i received the package on 14 november at 4 30 pm, but when i opened the package the product (Watch) was missing but the watch case and warranty card was present, the box was sealed well but for my astonishment product was not there

The delivery boy has not taken any signature when delivering the product, since the payment was made online, i opened the package after 15 minutes after the delivery was made

Please go through this case and help me find the solution