Buy and Get - no response!!

I purchased 4 Samsung Aircons in Nov 15 , specifically taking the Buy&Get promotion into account. I completed the on-line application forms before the deadline. I received an sms on the 18th of Jan to re-send my invoices, due to an ''error''. I resent the invoices on the 19th of Jan. A few weeks later (1st week of Feb), I received a call from an agent in the contact centre, requesting me to yet again re-send my invoices to them, as \they did not receive it\". I re-sent the invoices on the 3rd of Feb! After no contact / feedback for a few weeks, I sent an e-mail on the 27th of Feb requesting feedback. To date, I have received no response?? Guys, please can I have some customer service ???"