Keyboard not working


I m shweta , i m using acer aspire one d255 notebook , my system is not working well as when it starts it take long time to start n now the current prob is some of my keywords are not working i.e M, J,K,L,U,I,O,P . On these keywords numbers are also written startng from 0 to 6 and *. But instead of giving alphabets they are giving as numbers which i mention.... so now tel me what should i do... plz reply asap.