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My Samsung Galaxy Note 3 has begun dropping contacts from my phone list.  I will receive a text from a phone number and realize it is someone who was in my Favorite List and is now removed from contact list completely. Today three people that I call, message or email frequently were simply gone from my phone.   This happens intermittently and is random.    I believe it started after last update when other problems emerged. To stop phone from overheating I had to remove the cover.  I also had to remove my 32 Gb data storage card in order to get phone working properly.   Has anyone else had random contacts erased?   I've read about cases where all contacts were removed but my problem is different.   Thank you in advance to anyone who can help me solve this problem.