Pushing out

Shouldnt the balls rather go into the net if it was too flat?

That depends on how hard you hit it and the angle of your racket when you hit it flat. 

Maybe you are holding bat too tight, try shot with relaxed soft grip and see what happens, as well as experimenting with angle of bat, and brushing as  advised by AR.

It happens to me all the time even if I am trying to retract the hand on impact but the ball still goes out.
I know all these things regarding brushing,angles etc.
After all,I am a defender,I use pushes most of the time.
Also,this happens to me only last few weeks. Before it was quite OK. I havent changed anything in my technique and I cannot figure out what is wrong :(

DK, you should definitely try not to stress about this. I sympathize as last few weeks I can't seem to play a decent backhand either a flick, drive or loop against anything short on the table. This was and is my steady side that I usually rely on if my more attacking forehand starts going a bit wild. My point is the more anxious you are the more stiff your whole body will be and the more jerky it will make your strokes.

Clear your mind, take some nice deep breaths and practice, and practice more until you get back in the groove. Know that your pushes will start to work again.

Maybe it is related to by new teammate and the psychology he creates,and disturbs me.
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