I’ve used photorec with great success. Install it from your repos. It will allow you to select the device to recover from, and also what kind(s) of files you are looking for. That will help you with files which may be missing. (worth a shot, and should be relatively safe because it does not write to the partition it is scanning, if you don’t tell it to.)
If the physical media is damaged, you may need to try out dd-rescue to copy the partition from the damaged media to a file or other USB drive for further recovery attempts.
I’ve done these many times, and it has really worked well for me! HTH!
I haven’t tried this myself but looked it up a while back when I lost data on my flash drive I later deemed replaceable rather than waiting to install Linux on another drive. Here is the link to what I found hope it helps in someway.
It is really possible to recover deleted data from a USB or flash drive storage devices. It is also true that you can recover it even without any third party software both on Windows or Linux. However, this manual recovery of deleted files are not really that easy as you think, it requires extensive knowledge about the structure of the hard disk drive. It is still better to use a third party software to do the recovery of the lost data.