Xiaomi India — phone not showing 2nd sim

got all new mi 4i on 5/5/2015 from flipkart, bt as i put 2 sim sims in phone, phone not showing 2nd sim, tried another sim also bt. not solved. problem is in front part of sim tray, whenever i put any sim in front part of sim it does not pick up the sim and phone shows insert sim msz, bt when i put same sim in second part of the sim tray it works fine...plz solve this or exchange it