Please help

[simoncn]

Copying data from one NAS hard drive to another is tricky because each NAS has its own proprietary way to format the drive. The simplest way to is to set up a network share on the old NAS (you already have this) and access this network share from the new NAS as a remote drive. You can then use "File Station" (or similar) on the new NAS to copy the data over. It will not be quick but it should be simple and reliable.