My pvt. ltd company is not giving me relieving letter still I completed notice period of 1 month.

I am selected this year (2018) as Office Scale 1 in RRB Bank PO.(Government Undertaking Bank) I submitted fake private company relieving letter at the time of interview (I was having company letter head, I typed, I signed, without company seal and submitted, but I really worked there for 10 month 17 days including notice period. At that time (17-04-17) my company agreed to mail me relieving letter, but now (about 7-02-18) saying ''I left Job in probation, so relieving letter can not be issued and also making baseless allegations about site problems and will not give relieving letter. My boss says that he will only speak in my favor with my Bank HR to confirm that i am relieved.) After asking too much, saying I have too much of need of relieving letter, my boss is asking me to submit 3 lakh rupees to him. He is now intentionally harassing me. -I was not taken photocopy of my resignation letter that I had submitted on paper to my boss around march 2017 end. I asked for photocopy of acceptance of it but my boss saying that he had scraped that. -I Have offer letter of my private company -I have bank statement of my salary -Notice period is of 1 month but my boss relieved me after about 17 days of notice period -In between [deleted] to now, I was preparing for bank competitive exams -My bank Job joining Document Verification will be around 5 April, 2018 As per bank rule joining will not be given without relieving letter. I want to take back my fake relieving letter to avoid any future problem and finally want to join bank with proper manner. Please help me