Have you received any notice of lien on your savings bank account from Bank in writing ?
If not, first issue a cheque for Rs.2,000/- to any of your close friend or relative and ask them to present it to bank, and if it is returned, ask him to insist with a covering schedule showing the reason for such return of the cheque.
Then armed with it approach the Bank and ask reasons for noting the lien.
The Bank exercise their right of general lien on any account , if you are a borrower or if you have guaranteed to any third party only. Even for that serving registerred notice is mandatory.
Then file applilcation seeking information under RTI Act, seeking specific reasons for returning of Ch.No....given to a third party, when the outstanding credit is approximately over Rs....
Armed with all documentary evidence, contact any Advocate and explore remedies, if the Bank is unreasonable.