i have had this for about 6 months and instead of setting the display off timing as a short time i set it at 30 minutes...and kill the screen by clicking the top side key lightly...as if i was stopping a call as well

lately the phone has been going off intermittently
so
either i am holding it a bit too long or the switching is not goog

may i please have any input onto what i should do

i thought just setting the screen off timing to say 10 seconds but dont want it going off as i am reading a bit of script etc

cheers
geof