My Nikon D750 won't record videos

[cheryls]

There's this logo that says "no rec" On the top of the live view mode, I've switched to recording mode, reset my camera settings, try to take my lens off and then putting it on again. But the red dot that says "rec" Won't show up, what should I do?
Please kindly help me, this is kind of urgent

 

[nikonpup]

 

[cheryls]

I tried to reset it, it worked again for a while but then it won't record again. But this time, there is no the "no rec" Symbol on top of the movie live view I keep pressing the record button but it won't work, the card that I'm using are the same ones that usually worked (lexar 128GB)