OVERWRITTEN data cannot be recovered, as it has been physically (electronically) replaced with something else.

Dr. Peter Gutmann (University of Aukland, New Zealand) wrote a paper on this around 1996, when HDD technology was very different. His paper only referred to electro-mechanical hard drives, rather than solid state drives that use transistors as opposed to magnetic media.

You can frequently recover "deleted", or "lost" data because it is still physically present; however, once it has been overwritten (replaced) with something else, it is GONE FOREVER.

None of the snake oil products suggested by spammers can do a thing about that!