Error 354 represents a big problem with your device's operating system (OS) software. More than likely, there was an application that caused loading problems with your device. You will need to wipe your device of all the data and reload the OS. After you load the OS, do not load any 3rd party applications until you let it run for a while, testing all of the features of your device. My suggestion would be to let it run for a day just to put it through the normal paces just to ensure all is well. Then, add 3rd party apps one at a time, checking after each installation. I hope this helps.