Hello users! I am using a Samsung phone and I transferred some videos to my flash drive from my memory card. I tried transferring it back but most of the videos vanished into thin air.

Meanwhile some of the videos that enters my memory card keep saying "File not found/file not supported" u know what I'm saying.

I cannot find it anywhere. I think it has to do with this LOST DIR folder because there are a lot of large files equivalent to the files I transferred! !! Someone should help me please because I CANT LOSE A 6 GB FILE!!!!! HELP ME RECOVER MY DATA ABEG!