After Sustained Writes The Drives Filesystem Corrupts, And Your Data Goes Bye Bye
A fair number of users of the portable SanDisk Extreme SSDs, specifically the 2TB and 4TB models of the Extreme V2 and Extreme Pro V2 are experiencing catastrophic data loss. It seems that after long sustained writes, the file system on the drive corrupts and all data is lost. In some cases users were able to use data recovery tools to regain at least some of their files, but many have not been able to successfully restore anything.
The majority of the complaints involve the 4TB SanDisk Extreme SSD and the Pro variant, for which SanDisk will be releasing a firmware update to resolve the issue. At this time there has not been any news for owners of the 2TB model who have lost their data. Unfortunately there has also not been any timeline given for the release of the firmware update for the 4TB model nor any details on what is actually being fixed. SanDisk have also not released any official policy on refunds for users who no longer want to use these drives.
If you have one, you should definitely back up everything on it to another location as soon as you possibly can.