Reliance Jio Infocomm — False promises

In My Jio app it is clear shown that if a recharge of Rs. 399 or more is done using Mobikwik, flat Rs. 100 would be given as cashback. Lured by such a promise, I did a recharge of Rs. 555 in the hope of getting the cashback. But after doing the recharge, I didn't get the cashback as was promised.
This is a clear case o[censored]nfair Trade Practices. If they don't want to fulfil what they have committed then I would also like to get the transaction to be reverted. I did the recharge only because of the promised cashback.