Byju's — initial fee is not being refunded

Address:

thiruvalluvar street , dhandeeswaram, velachery, Chennai, Tamil Nadu, 600042

Byjus employer has take initial fee 5, 000 with receipt. Rest to be paid when we confirm the order and tab will be delivered.
But after a week i tried to cancel the order and get the initial fee back.
None the classes been taken, i haven't even seen a teacher's face nor got any tab. For the first time this employee came and collect initial amount. Now we are struggling to bad to get that amount back.
They are refusing to respond
None of the complaint mail hs got reply, nor proper response from customer care