I have found echo devices to be fussy about which wifi bands they would connect to. I would recommend giving the 2.4G and 5G channels a separate SSID and trying each individually. I also found they needed a reasonably strong signal for reliable connection.
Thanks for replying back. Can you try doing the full reset on the Echo (using the little pin hole reset button on the underside) and make sure you are trying to connect to the 2.4GHz network as I don't think the Echo works on 5GHz. If this isn't the issue, try powering off the hub and power back on again, then try reconnecting.
@Minna1 I have just struggled to connect an Amazon Echo Dot (2nd generation) to my Virgin Media Hub 3. When scanning for network ssids it showed my home VM wifi as a very weak signal and wouldn't connect. After trying various reboots etc I selected the option to Add a Network and typed in the SSID for my VM wifi followed by the password and selected the security type and this time it connected without an issue.
So worth trying to add your network via the manual route.
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