Brightness on my iphone isn't showing up? - 1

I dropped my phone in water.got a new battery put in it and it worked fine.until i turned down the brightness and now my phone is completely dark and i can't see. It still works i just can't get in my phone! What's going on? How could i fix it? Is there a reset button?

Added (1). What does it mean to format it?

Try pulling the battery out and put it back in.

Just format it

Try to format your iphone, If it did not work update or change the software of your phone, If this process also did not work just change the display of phone. Hope i helped!