Consumer Redressal

I have purchased a smartphone model iris x5, from M/s. Bhajanlal Commercial (P) Ltd on 17th Oct, 2014, vide invoice no: 9310. But using the same post 15-20 days I have noticed a distinct cracking sound while using the phone from the speaker. Hence I have been to the service center M/s. Mobitel, Kolkata. They took my service request vide work order no: 510002359134 on 9th Nov and repaired the speaker. But after the delivery I have noticed that there are huge network issues and once again I am unable to use the phone as there is no network available in the handset. On 11th Nov again I have submitted my phone vide work order no: 510002377115. at 3.30 pm. But till date they are unable deliver the phone and there is no clear cut communication, only received phone calls from their service executives stating it is under repair and will be delivered shortly. Now either they should refund the money back or replace with a new handset, but there is no reply from them.