There are not enough details on your experimental setup to really answer this question. What was your offset, what is your sweepwidth, what concentration of TMS have you used, in what solvent?

Respected Sir I can send you a spectra. Maybe you can find more information. This is HNMR of an organic compound. The solvent used is DMSO. however we can see a strong peak for DMSO. TMS is internal standard. I am not sure about the concentration of TMS.

Dear Muhammad, TMS is volatile. If it was added during the extraction and there are evaporation steps there is possibility that you have just lost it. A blank sample with TMS added right before analysis would verify if your settings are ok for TMS detection. In that case you should add TMS with the solvent in which you are resuspending your sample (e.g. deuterated chloroform) before analysis, for calibrating chemical shift for 1H, and use another internal standard not volatile during the extraction.

Muhammad,

I do not see anything weird in the parameters of your H NMR spectrum. It seems that there is no TMS in your sample. As Andrés mentioned, it may be that you added it, but it was evaporated before the sample got to the NMR spectrometer. In principle you can use external TMS, since you have a DMSO peak and you know the temperature of your measurement, i.e. 295.4 K, for temperature correction of the solvent shift.

http://wiki.epfl.ch/nmr/documents/1H_2D_TMS-ref.pdf

This paper should help you to correctly calibrate your NMR spectrum based on the DMSO peak.

I also do not see anything unusual in your experimental setup; the DMSO peak is clearly shown in about the correct position, and there is obviously no TMS signal. As pointed out by Andrés and Sander, if you did add TMS originally, it must have evaporated before the spectrum was recorded. Do check out the paper Sander suggested, it is a very good guide for proper referencing. Good luck in your research!