Bajaj Finserv — To refund my money

I had applied for loan of rupees 20000 in Bajaj finserv and then they asked to pay 1500 as a loan processing fees I paid them and before sanction of loan amount in my account they asked more fees as a gst tax and said them to cancel my loan because of so many taxes.and said them to refund my 1500 of loan processing fees which is refundable but they are denying to refund