HappyEasyGo — refund not given

I cancelled a ticket booked through happyeasygo.
They asked me to forward cancellation mail from airline. I called them after sending and a representative informed me that refund amount (1622) will be refunded within 7-14 days.

I've received 100 p. Person from them.

They keep me on hold for eternity while calling and respond as "we are working on this query" while emailing.
They charged almost 93% of refund amount saying its a service charge which they can't even tell me how!