Looks like the driver is unable to read the MAC info from EEPROM. I know it was working before, not sure what went wrong when the server was abruptly went down.
Check the card health state.
Try installing the OS again and check.
if possible, add this card on another server and check if it works well there.
Unfortunately I haven't got another server to test the card on.
I've ordered another card which should come tomorrow, so hopefully that will work.
Installed the new network card today and it works now.
Thanks for your help.