Byju's — Want to discontinue daughter's subscribed course.

I have taken a 3 years course for my daughter of class II, from BYJU's. Initially, I have deposited Rs. 5000/- and received the course material for class II. I have already cleared 5 EMIs - paying Rs. 4, 172/- monthly.
Now, I am facing financial difficulties and will not be able to pay such a huge amount on a regular basis.
I have approached their Guwahati office and told to stop the course at class II and asked them how much I have to pay for it. Instead, they have told me that it is not possible to dis-continue the selected course in mid-way and I have to pay all the dues without fail.
Kindly suggest & guide in this matter.