My WDBCTL0030HWT 3TB My Cloud Formatted Itself

My WDBCTL0030HWT 3TB Formatted itself without any warning can I restore my files ? I haven’t touched the drive structure since it rebooted ? but if I log in nothing is there ! Any Ideas

Why do you think it reformatted itself?

it looked like it rebooted itself so then when I logged in it told me it was formatting !??

Can you SSH into the device? Use the ps -eaf command to see if a format is running. If the data is mounted use the df command to see if the disk is mounted and how much space is used.