Mobikwik — Late Fee charged

I used the Mobikwik Zip payment service to pay for an online transaction. I had to pay the bill amount of 3140 on August 20th. But the repayment system in the Mobikwik app is not functioning correctly. The transaction was always failing. The very next day they charged me with a fine of Rs.500 for the delay in re-payment for which the reason was issued in the payment process of the app. I had raised a complaint regarding this for which the support I received was delayed and incorrect. Even after this, the company is asking me to pay a late fee of Rs.641 now and threatening to charge another Rs.500 if I don't pay the bill and fine before September 1st. They are not addressing the complaint raised and not waiving the late fee, which shouldn't have been charged since it was a mistake on the company's end. The company is threatening to report to CIBIL and asking me to repay the amount including the fine without listening to the complaint raised. I would also like to point out that I raised a complaint regarding this a month ago as well when the same issue happened.

Twitter thread- https://twitter.com/MobiKwikSWAT/status/[protected]