I had just about the same thing happen to a friend’s Hub. This is what I did:
Pulled drive from the Hub and put it on a USB adapter to the PC
Backed up ALL the files to another drive
Used Windows Disk Manager to delete ALL partitions on the drive
Removed from USB adapter and put it back in the Hub with NO partitions on it
Allow the Hub to partition and format it using the Hub’s Disk Manager
When completed put it back on the PC put your files back on it and put it back in the Hub
I think I also did a full reset on the Hub as well
