Myntra.com — discount coupon/ unable to contact

Address:

B.J.S., Jodhpur, Rajasthan, 342001

Hi,
I received a discount coupon worth rs 400 from myntra. Coupon said you have been away from myntra and thats why we give you rs400. I did my purschase and applied the coupon that very day and it said it is expired.
I am trying to contact them but there is no way you can do that. There phone number on the website is always switched off. There is an option where they call you back, but they call you once in 10 times. They say we are resolving your issue and will call you back. But they never call.