Demand showing on pan

The most important point is whether you have the TDS certificate with you or not. If you have the same, file a rectification petition U/s 154 along with the copy of TDS Certificate. If you do not have the TDS certificate, ask your employer to provide you with the same. Or, ask for even a salary ledger in which deduction of TDS has been reflected. If the TDS amount is large, you can file a criminal case against the employer company. 

Please provide details of your case in my e-mail I.D. raghavsbp @ gmail.com so that a more accurate opinion can be given