Thank you for your valuable advice. After some changing in advanced tab I got some partial result which is followed the trend of 2D simulation but the simulation stopped at 76%. I am not sweeping over a range of voltage because it takes huge amount of time only simulating at target bias voltage to see how it follows 2D result. Maybe this is creating problem?
*previously I have designed another photodetector following the example of vertical photodetector given by lumerical and also simulated vertical detector in 3D. That time 3D simulation ran smoothly but I had to put a material in background material settings in the simulation region tab otherwise, the simulation didnt ran. But 2D and 3D result didnt match both the times. 3D current was almost 10 times smaller. Do you have any idea why this happened?