phones are working but the screen is black

my oppo reno 2z slipped from my hands (only from 12 inches) one corner of display where the headphone jack. and at that time i was using ear phones and luckilt it falls on my foot.

now the function of phones are working but the screen is black. if i press its 4 corners of display panel the picture is very dimm we can see its display in dark. however, the password pin/pattern and th upper side of screen where battery , time blue tooth signs are very clear and we can see them in day time. the phone some times blinks on pressing

now the brightness function is not working and touch command takes 3-5 seconds to execute