Click Settings in the Epson ScanSmart window > Scanner Settings tab > Change to confirm or re-pair the scanner using your computer.
Make sure another computer is not connected by USB. A USB connection takes priority over a Wi-Fi connection. If another computer is connected by USB, disconnect it.
Make sure Epson ScanSmart and other applications are installed correctly.
Check that the Wi-Fi connection is working correctly.
Try turning the wireless router's power off and then on again.
Make sure that you select the correct scanner.
Click Change in the Epson ScanSmart window, select your scanner, and then click OK.
For Mac OS users:
Make sure you select the network that has priority on your Mac OS.