Byju's — Subscription Cancellation request

I would like to cancel my subscription for my son for the course - class VII - NIIT, JEE because at the time of registration the executive told my that I have to pay in 5 years instalments but now I got to know that it is of 1 year EMI plan, the amount per month I can't afford at all. My EMI will start from JULY 2022. He misguided me and I am very much worried now.

Secondly the Tab they gave is not working from the first day (the learning app is not responding) so the whole process of learning is of no use.

Please cancel the subcription as early as possible.