Income tax not deducted by employer

I would be ul if someone can give me advice on the following incident

I am working for a PSU. I worked in a particular location for 5 months and then was transferred to a different location. My tax was dedcuted regularly for the first 5 months but in the new location for the next 6 months no tax was deducted. I had enquired about it twice and go to know that the payroll code has changed so the person looking after tax here cannot see my full schedule of income. I got the schedule from the SAP team at Head office and sent to him requesting him to do the needful. But in my March 2014 salary slip also there has been no deduction but my schedule shows that i need to pay 21000 nearly . I have written it to the concerned people in my organization but till today nothing has been done. I would be grateful if someone can tell me what do-Shall i pay self assessment tax online or is it the employers liability to pay the income tax.