You should have filed
RTI application with Indian Postal Order of Rs.10/- and hence
PIO/AA are silent. They do not guide you on correcting defect in applications. IT Dept is under central govt. and hence rules of central govt are applicable. Pl visit my recent blog for refund of Income Tax and refile application accordingly. If you have lost ackt-copy of return, send copy of income tax return or details of date/month of filing, so that they can trace at their end. I think in 2001-02 dept was not fully computerised and hence locating the same would be difficult. You may ask for inspection and help trace out the original return etc. The dept maintains a register containing details of returns filed in chronological order. U can locate your return filing details from this register.