Fraud done with Consumers by Yu televenture

I have a yu yureka phone.
After lollipop update my phone’s flash is not working well. When I complained about it they told me to mail them the order id, purchase date , issue date etc and they will replace the phone.
I have done all that and since 5 days no reply from them.
Ihave got cheated andwant my valuable money back or to replacement of the device.