1. Does the title of the property stands in the name of your mother?
2. If yes, then the Bank will return the original title deed of the mortgaged property to your mother being the title holder of the said property.
3. Even if you have paid of all the dues of your father's loan, you can not claim delivery of the original title deed of your father's loan.
4. The above advice has beeb provided considering that your father is no more and if he is alive, he shall have to approach the Bank to get back the title deed.
5. If the Bank refuses to return the title deed to your mother, she shall have to file a Writ Petition against the Bank's inaction praying for a direction upon the Bank to return the original title deed to your mother if the loan taken by your father has been fully paid of.