How to Completly wipe data from My cloud home

Dear All,

I want to sell my My Cloud Home, and I want to delete/wipe all data, before selling it.
I already followed the steps in the below link to Erase All Data:

But I don’t like this Statement “Data Recovery may be possible using a WD Data Recovery Partner”
Do you know any network drive “file shredder” able to do this? or any way to do deep formatting for the drive?

Thanks a lot for your help.

You need disassemble it, and save current contents to disk image. Then deep format the hard disk. Finally, restore the disk image.