Kotak Mahindra Bank — Payday loan scam

I was initially advertised about a payday loan showing a tenure of min 10 days repayment, no where it was mentioned that it is only for certain number of days i applied and took the loan and on the final page missed on checking the repayment date as i trusted the ads they showed me before and layer realised i have to return the amount with interest and other charges deducted i dont find this tenure game fair and feel cheated by the bank, if I could make 8000 in just 3 days why would i take a loan? Please help