Thanks, Viper and Zabuza.
It's OK now. I figured it out. Because after the patch, the flight model is more realistic now, but I was still landing like the old days. My tail ended up on the ground before my wheels. And the landing circle is now positioned in the middle of the run way rather than on the beginning of the run way. So all I had to do was to fly slightly below the guided path and on pitch up a little right before the touch down to reduce my vertical velocity (because the guided path gives you about -5 meters per sec, if you follow it, you will crash).
But still, thanks so much for your kindness and trying to help me. Much appreciated. :)