newly installed apps diappear (opens in new tab)

dear all, i have been using android smart phone for 3years now\. few days ago my android broke down\. as i started it, I got \"android recovery\" message and \"factory reset\" option\. after trying with some professionals, i did a \"factory reset\" due to which my useless data got deleted\. after resetting , i installed my required APPS and set them to run like logging into them\. i did the reset and installation 2 days back\. but today all my APPS which I installed got deleted\. could anybod...