The Digital Controls app shows 10 Wi-Fi network, if your Wi-Fi Network is not shown try to refresh list scrolling down the page of Wi-Fi Network.
The Voice Control Alexa cannot access the Internet via a public Wi-Fi network (hot-spot) or via a company Wi-Fi network, and these networks are therefore not suggested. If your personal Wi-Fi network does not appear in the list of Wi-Fi networks suggested, first check that your smartphone is within range of the Wi-Fi network, and move closer to the Internet router if this is not the case.
If your Wi-Fi network still does not appear in the list of available networks, it is probably because it is hidden: manually enter your network's SSID (name).