Text are inverting, breaking...pls give me solution

Last couple of days I am facing with my cell NOKIA 3310: Often its screen goes down, though charge is full, I can see the text of the cell reverse and break down the text, even I (Not only me, anyone) cant read the text, I cant read who is ringing. Can anyone help to resolve this problem and how (pls step by step)? I have data cable for this cell. If I do SW reset by Noktools (by rolis v 1.9); relief me from above problems for a few hours. But the problem start again. :-?