Resignation from the nationalised bank(bank of Maharashtra)

Dear sir , I was working as a PO in bank of Maharashtra.date of joining November 2014. Last year on 8 July 2016 I took leave for 9 days from my branch but couldn't not rejoin services due to personal reason (ill health and also fed up with the type of job) . I sent an email to my branch manager on 01/08/2016 about my poor health condition and also that I will not able to rejoin my duties for some days . On 20 December206 I received a show cause notice for absence then I send a resignation letter and also email informing about my resignation in December 2017. In Feb 2017 I also enquired about any formalities but no response came from the bank. In February 2017 I applied for upsc civil services examination and also appeared in mains examination this year. Now again this year in November I applied for resignation from bank but my branch manager is not forwarding my resignation letter to higher authority. Now I am worried about my upsc interview as I have not been able to get relieving letter from bank in time.Please suggest what should I do now . I know there is some lapses from my side but whether it create any problem in getting relieving letter from bank or appearing in upsc interview .