My phone started having problems yesterday morning. It was in a loop showing applying android updates. I went into recovery mode and reset to factory settings. Then the phone worked properly for a while until play store indicated it was not working. I tried downloading another version of play store and my phone broke. It went into an endless boot loop. I have used Odin to flash the ROM and now I the phone is stuck on the boot screen showing the Samsung GALAXY light SGH-T399 logo on the screen.
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