WD My Cloud Home Device Offline

Try disconnecting the MCHduo or try rebooting the router or try to connect the unresponsive MCH single to the WAN port of the modem directly. It is also possible that there is something wrong with the OS boot HDD of the My Cloud Home which may be a SMR drive and is not generally usable in a NAS or OS environment and your unit could be more than 3 years old and has too many unrecoverable errors.