State Bank Of India [SBI] — Not closing loan account even after paying all EMI

I have taken pension loan in SBI. Last month, the tenure of loan is completed leaving with a balance of 1448.12. I tried paying complete amount and close the account but the system did not allow to pay complete amount and as a result, I paid 1447 and for remaining 1.12 rupees, I logged a manual closure request by checking the option to debit the remaining amount from my savings account through net banking. However, they did not close the loan account and in return charged 6 rupees interest and held an amount of 9600 in this month. I again paid 6 rupees and repeated the process that I done for manual closure (as again the system is not allowing to pay full balance). I don't understand why SBI people will not take prompt actions and with hold our money and again charge interest for no reason. SBI needs to improve their services a lot. Its been 3 days since I raised manual closure action and the action is not taken yet.