seema: your regulator is probably not defective, but as stated your design is not good . you can either select an input supplut at a lower voltage, measure or calculate your true load current, and using that current calculate the proper value for the series droping resistor value but not wattage rating remember that under short curcuit conditions the regulator will try to draw up to 1.5 a so your wattage rating should take the maximum current that could flow under this condition . next as advised use a minimum load esistor to stabilize the regulator under light load. and finally use a heatsink as this will reduce instability and drifr=t that results from temperature excusions. finally go to a source web site and download the data sheet then read it as most of the problems that you have are fully dealt with in the data sheet. Terry