Income tax return for salaried person

Dear professional, please help me on the following issues: My father works in a PSU, thatis his only source of income..So I filed his Income tax return based on the salary certificate issued by the employer and obviously there was no refund or payable(A.y 2016-17)..But i received intimation u/s 143 from the dept where they have calculated a demand for Rs 34000. On sudying the initimation I came to know that they have not accounte the relief u/s 899 relief on arrear salary) and tds paid by the employer ,that is, TDS u/s 192(1A)..but the same tds has been shown in 26AS...so i requested them for re-processing but again I have received an intimatio u/s 154 showing the same demand..I called them up on the CPC toll free number and one of the personnel told me that it is possbl that the Form 10E which is necessary for claiming the relief has not been filed...Nw pls guide me on this..that who is laible to file 10e employer or the employee and by when..and how can i get rid of the deman..plese help me