This is a by-product of the way that the underlying Linux system implements move.    It first tries to do a ‘rename’ if it thinks source and target are on the same Mount point and only if that fails does it do a copy/delete.    In this case both appear to Linux to be under ‘mnt/user’, and so it tries rename which has worked and the file is left on the cache.    In such a case you either need to have the target set to Use Cache=Yes so that mover later moves it to the array, or do an explicit copy