1. It appears that since your mother predeceased your father then while he was alive he may have named you as your nominee.
2. File an R.T.I. to get such confirmation whether you were named as a nominee.
3. In case you are your father's unmarried daughter (irrespective of whether major or minor in age) or minor son or unmarried adult son then you can contest of non release of retirement benefits of of your father by filing a writ petition before the H.C. or before the state/central Administrative Tribunal even if your pleading before the N.H.R.C is pending.