If it wasn't a full format the data can be recovered. I recovered 2TB of data like this:
1) ran "EASEUS Data Recovery Wizard Professional"
2) used the most advanced option to SCAN my drive and detect files
3) Files were then copied over to a SECOND drive of equal or greater size than the recovered data.
*So you need this program and another drive. Other programs might work but in my case I went through 8 programs with no luck. However, I hadn't accidentally formatted my drive but rather the drive was somehow defective but still able to scan for data.
Since your drive is NOT DEFECTIVE, you would then:
1) run a FULL FORMAT on the previously formatted drive (formats AND builds a bad sector table), then
2) COPY the data back over (or just leave it where it is on the second drive)