Do contact Federation of Malaysian Consumers Association immediately, http://www.mypengguna.com/mypengguna/index.php/hubungi-kami they might bring this matter to a tribunal to protect your rights. They might urge the shop to give you a full refund. Don't do anything on your phone first keep it as it is..

Cheating is also a crime, you can lodge a police report at the nearest police station.

Do share your experience with the public by writing to NewStraitsTime, SinChewJitPoh and Berita Harian...
you should determine to tarnish the image of the shop as all of us abhore irresponsible retailer...