Sac code for small railway e-ticketing agency

I run a small business in Robertsganj, UP(East) and voluntarily wish to register for GST. I'm basically dealing in two types of work-

1). Railway e-ticketing from IRCTC website - I charge Rs. 40/- per ticket as my agent commission/charge.

2). Online funds transfer and school fee payments etc. - For those who earn here and send some money home. My charges Rs. 40 - Rs. 100, as applicable.

I wish to know what SAC code applies for my category of business. for GST registration. I've annual business of about 15 lakhs.