Symptoms suggest a failure of the network connection; the Ethernet port on MyCloud, or Ethernet port on router, or Ethernet cable. Try a different router port, and a different cable. If neither of those helps, recover the data:
A MyCloud you buy today will get a Gen2 hardware, with v2 firmware. Your three-year-old device will be Gen 1 hardware and v3 or v4 firmware, and will not work with the new hardware.
