About 2 years ago I purchased a then-brand new HP 12C Platinum. After about a year or so I noticed some of the number keys had become crooked. Some were very loose. Over the last year this has become worse, and to make it more annoying some of the buttons (usually some numbers & operator keys) have become unreliable. Sometimes the keys work, sometimes they dont. I'm pressing some keys harder than I should to be sure they actually register and show the number on the screen. Some buttons dont click anymore, and barely move when I press them. Its like they're pushed in already and you have to press them the right way to get them to respond. This is very annoying. Other than buy a new calculator (I need a 12C for the CFA exams), is there a way to fix it? If not, should I buy a new one, ie 12C instead of 12C Platinum? Thanks.