HappyEasyGo — total refund was not given on flight ticket cancellation

I booked a two way ticket from happyeasygo on 26th july (Order id:[protected] as below

- delhi - hyderabad 3rd aug
- hyderabad - delhi 3rd aug vopjfh

By mistake i selected the same date for the returning ticket and i notified the happyeasygo cc team within minutes. They denied to help me in this regard and told to contact vistara cc team and then contact heg again. I called vistara team they cancelled the ticket and told that 2620 was refunded to heg and you will receive the same after deducting the convenience fee (230). But heg returned 1481 only.

Here is refund breakup provided by happyeasygo:

Airline's penalty: inr 1000
Happyeasygo's service fee: inr 1000
Convenience fee: inr 230
Ticket cost: inr 3, 711
Refund amount: 1481

Happyeasygo's service fee: i don't know on what basis they deducted 1000rs even when they did not provide any service on cancellation, i want this money to be refunded as well