iphone freezes after being locked for a few minutes

[emerica6708]

idk if this is a problem that can be fixed or not. it just happened all of the sudden i hadnt restored or updated anytime when this happened but the phone works fine just like it always has but if i lock it and leave it like that for a few minutes i cant unlock it or do anything i have to hold the home and sleep button to resart it i can lock it and unlock it fine as long as i dont keep it locked for more than three or four minute. i had 1.1.4 when this happened and ive tried restoring it upgrading it and downgrading it but nothing works. any help would be greatly appreciated

[beachboarder41]

Wait, are you on 2.0 or 1.1.4?