LittleApp — deal cancelled but cashback not credited back

Address:

Mumbai City, Maharashtra, 400069

I had purchased a deal on little app for one vendor named cafe bliss for 330 rs on 29th June using 300 rs for my cash back received from my previous purchase and paid 30 rs through my credit card
I visited the vendor on same date i.e 29th June and found that the vendor had closed the outlet
I complained about it to little app on same day, they after 2 days refunded back 30 rs back and forfited my cash back of 300 rs
It is the policy of little app that if the client cancels the deal their cash back dose not get credited but in this case the deal was cancelled by the little app themself as the outlet of vendor was closed so I should get my cash back back into my account
Help me get it back