If the step/s you are taking now don't work. There is a chance the drive maybe failing. I have had WD drives fail within weeks of purchase and for me never again.
As the drive is possibly under the 12 month warranty take it back and say it suddenly stopped working and they should replace the drive without to many hassles.
Prior to the above copy any data that you can.
Also another option to try which may work by the off chance is to find someone with a PC and format...