Folder in pendrive shows empty

Hello,

I am using HP 64 GB pendrive and formated to fat 32 from exfat. when I insert this pendrive in any computer and copied filed to pendrive disappears when I click refresh or eject the pendrive

Under properties it does not show any used space

I tried several things without success including the following:

-Made sure “show hidden files” was selected under Folder Options
-Ran “attrib -h -r -s /s /d f:\*.*” in Command Prompt (it shows file not found g:\*.*)

I tried to reformat from the system to convert the pendrive to exfat. but it failed.

Now my pendrive not detecting.

Please help