Your computer or Epson software can't find/recognize the Epson printer. Usually a driver, port, or connection issue rather than hardware.
Work through these in order; most people are fixed by the first two or three.
Install the latest driver (and Epson Scan 2) for your exact model and OS, then add the printer again.
Confirm it's online and on the same network; if the IP changed, re-select it. For USB, try another rear port and a known-good cable.
Permit Epson software in your firewall, or test with the firewall briefly off.
On Windows, restart the Print Spooler service, then re-add the printer (by IP if needed).
Browse step-by-step setup guides, error-code fixes and driver help for every major brand sold across the USA & Canada.