Bajaj Finserv — signature forged in loan agreement

I have taken a flexi personal loan from bajaj finserv in feb 2019 since they were calling me everyday explaining the advantage of the flexiloan, where i need to make only interest payment for the 1st 24 months with nil prepayment charges. All the documents were submitted and they never asked me to sign any loan agreement. When i asked for it, they said that mail confirmation is sufficient. After making regular interest payment for almost a year, i was shocked to see annual maintenance charges being levied which was never discussed or informed.

I called the customer care inquiring the same and they informed that it is mentioned in the agreement and i have signed it (Which was a trigger point for me). I retrieved the documents online and was shocked to see my signed forged in the agreement in all pages and details were filled manually. Please look into it.