Have you opened a Support Case? If not opened, for more information, please contact the SD Technical Support team for best assistance and troubleshooting:
Recovering from the SanDisk Ultra drive is easy, all you need is a recovery tool. You can check Rescue Pro and Recuva, these are free tools that can recover files. In case of permanent deletion, these tools may not be useful for recovery, so you can opt for Stellar Photo Recovery, this software can recover the photos from formatted as well as permanently deleted files quickly.