Refund of Closure of PPF account (NRI) before amendment dated 1-8-2018

Dear Mr. Sreekanth Reddy, I am retired 60+ year old.  My PPF account was matured and I extended it up to 2019. My residence status is NRI since 2011. After the PPF rule amendmenmt dated 3rd oct 2017, I was in India in the month of  December 2017. During the visit I closed  my PPF account in Bank of Baroda, Mumbai on 28-12-2017. The Bank deducted interest earning from PPF account closure amount by reducing interest rate at 4%, effective from the date of my status change i.e. May-2011. The amount is in couple of Lacs Rs. I happened to read your blog recently, after reading your reply to Mr. Khosla on forum, dated Feb. 4 and 11, I understood that the amendment dated 3rd Oct 2017 is effective from the date of issue of amendment and not retrofit from the date one becomes NRI. My Question is: 1) Is bank is bound by the new rule to return my over deducted amount based on the amendment dated 8-1-2018 ?(link on your replay). 2) Am I eligible to claim over deducted amount based on PPF  amendment dated 1-8-2018 ? 3) Will you please guide me How to process refund claim from the Bank ? Thanking you. Vasant March 7, 2018.