Have you tried restarting it? It may just be glitching out.
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Have you tried restarting it? It may just be glitching out.
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[Edit] I have an old kindle fire hd, and after a year or two it started to glitch out. It stopped after doing a factory reset. If you have only books saved to the cloud, then it should be fine to factory reset, as the books can be reinstalled without purchase. If there are other applications with saved data, you should backup the information that you want to keep.