Manual position doesn't work

[paulyguamanq]

Hello everyone! I am new here
I am having trouble with my D5100! I have this camera for years, I used it in my office (i am a dentist). Suddenly, it stop working

I always take intraoral pictures in F20 - 1/125 with twin flashes. But now I take the picture, flashes go on but the pictures appear black.

Help me please!!!!

 

[Space Face]

Hello.

 

[stk]

Try removing the lens cap!

Are you sure your settings are correct, in both the camera and the flashes? This could be the result of a shutter speed faster than your cameras sync speed or just really underexposed images.