Selling faulty openview decoders.

Bought an Openview decoder there.After 3 months all of a sudden it shows,no signal,no channel.The manager refuse to send it for repair or exchange the decoder.He said I had to bring it 7days after purchase.I only needed an exchange of the decoder or a new one that is working.They refused to help me and said that I must send it for repair on my own cost.