Byju's — cancellation - invoice no byjus[protected]

I wanted alternative to tuition for my daughter of 7th class and installed byju's mobile app, immediately from next day every day byjus representative use to call to take their product and tried convincing me. Finally they convinced me saying their representative will come to my home just meet and hear him and can decide if to take their product or not.
A guy came to meet me was so sweet in speaking and convinced me to try their product for 15 days and said we can cancel the program with a single communication to them for cancellation if not satisfied within 15 days of receipt of product and they will not charge single rupee if cancelled within 15 days and took authorization of 24 months emi for rs. 60, 000 through my credit card.
I tried but it was not to our requirement and informed byjus to cancel the subscription within 15 days. Every day i use to send email / call them to cancel the subscription and cancel my emis on card but their staff every time use to say internal approvals are pending, post this it will be cancelled (Their will be no update from the their end, everytime i have to approach them). They dragged like this for more than 20 days (After intimating about cancellation). Finally they asked to courier the product and courier charges will be refunded. By this time my credit card bank has debited two emis and i had to pay the amount. Byjus confirmed it will be refunded and they took my bank account details.
I had returned back their product. Now smartly they paid rs. 51k to my bank account when i asked what is this, they said this is their program amount refunded but when i asked invoice / authorisation on credit card was for rs. 60k and why rs. 51k is refunded. They said the difference is the interest on their program of rs. 51k which i need to bear and pay to bank.
When i asked i have given for emi on credit card and not cheque / dd / cash why they are paying cash to bank account they said it is their policy.
I asked byjus to send cancellation request of emi on my credit card to my bank and no need to transfer amount to bank account now they said my credit card bank is not accepting their cancellation request. I had contacted my credit card bank and they said their is no request from byjus for any cancellation of emis, i called again byjus and asked to send the proof who rejected their emi cancellation request so that i can check with my credit card bank as my bank said it is ready to accept emi cancellation request of byjus, if received.
Now they sent an email with all the charges and penalties that will be incurred if emi is cancelled when i asked for proof of emi cancellation rejected by bank (But proof of emi cancellation request is not sent in email).
I again sent an email with the request to send below.
- the guy visited and their documents said if trial program is cancelled in 15 days their will be no charges then when i cancelled in 15 days why i should bear all these charges.
- there is no delay from my end, i had intimated within 15 days then why should i bear the charges.
- i asked for their terms & conditions and proof of my acceptance where it is mentioned that even program is cancelled in 15 days i have to bear all these charges and penalties.
- proof that byjus had contacted my credit card bank with emi cancellation request as they are repeating that their request is rejected by my credit card bank.
Already 3 days have passed after request but their is no response from byjus end as usual. When asked for escalation team details they will not provide and these details are also not found on their portal
I want total amount of rs. 60k to paid to me or cancel all emis and refund for already paid emis or provide proof in their terms and conditions that penalties and charges are applicable even if cancelled within 15 days. They are cheating with hidden charges and unfair practices.
My email id is "[protected]@yahoo.com"
Regards
Vamshi