Time keeps changing on iPhone?

My iPod touch 5th generation with iOS 8 is just not keeping track of time accurately when it is locked but fixes itself whenever I manually change it. I don't know what caused this problem since I have never changed my timezone or clock settings. It just stops keeping track of the time when I lock it. And now I can't even have it set to "set automatically" because the spinning wheel appears and does not let me choose my timezone. What can I do to have this stop happening? Is this a bug or is there something wrong with my iPod?

Reset it