EaseMyTrip.com — Customer request negligence causing refund money from air carrier

I had booked an Lufthansa flight ticket via EaseMyTrip.
I flew one side with the ticket. However, since the return journey was beg constantly rescheduled and cancelled by Lufthansa, we requested a cancellation and refund of the second part of the journey.
On calling Lufthansa, they mentioned agreed for cancellation and refund for the ticket but since the ticket was booked via agent site i.e. easemytrip [EMT85898751], they requested me to ask the agent to call on the Lufthansa dedicated hotline for agents and request for the refund. This according to Lufthansa was a 5 minute job.
Its been 1 month and after requesting easemytrip via calls and mails, they have not taken any appropriate action to request the refund. The flight date is already now in past and Lufthansa mentioned, that no one from the agent website contacted them for refund.
They have been negligent in responding to the request and making any effort towards refund request, which costed me half of my ticket prices, which Lufthansa was willing to refund.