My WD Passport Easy Store 4TB doesnt show up in PC

HI, Can anyone help with this issue. I have a WD Easystore hard disk and it doesnt show up in My Computer when connected to PC. All I can hear is the drive motor in Hard Disk is keep drivng and a green light is blinking. Nothing shows up in the PC for file transfer. It worked fine and the next day it doesnt showed up in the drive management.