Whenever you see a problem in your Echo dot device related to Wi-Fi, it could be the worst situation for you. You can do it manually using this blog or through the technical team. As you are experiencing, your echo dot device needs an active wireless connection to speak correctly, access your instructions easily and distribute media as well.
You have to plug your echo-dot device into a power outlet to connect echo-dot to wifi, then you have to open the Alexa app in it. The echo dot device can be connected as a complete lot thanks to the dual band Wi-Fi network which can famously use 802.11a / b / g / n.