TL082 Voltage Follower
In case you run the TL082 on a single ended supply with negative supply at GND, the input of 0.5V could be below the acceptable level and cause a phase reversal. The datasheet states that the acceptable input common mode voltage is:
VCC- +2V to VCC+ +0.1V
If you cannot increase the supply range, look for more modern opamps. These can often work with inputs below the negative rail. If you need the output similarly close to the rail (as for a voltage follower), look into rail-to-rail opamps