I have connected once the Vss and Ground of my LM35 sensor reversely wrong. After correction of this, the output voltage is 0.5 V which seems to be invalid in room temperature. I'm not sure if the sensor has been destroyed because of incorrect connections. It is also important to know that I am implementing this sensor for the first time and I have never used it before. I would appreciate your ideas about this issue.
The LM35 datasheet says absolute maximum rating for supply voltage is -0.2V.
It means that connecting it the wrong way to a power supply can damage it, and it does not have to work any more as the absolute maximum ratings have been exceeded.
Also the minimum recommended supply voltage is 4V, so check that your supply voltage is also 4.0V or more. It may not work properly at 3.3V.