New Xenon can't connect to cloud using Argon

I successfully got my new Argon to connect to the cloud and breathe Cyan. I got my Xenon to connect to the Mesh network, but it doesn’t complete the process of connecting to the cloud. Similar to this problem: Xenons not making Cloud Connection via mesh They Argon and Xenon both reset at one point, the Argon blinks green for less than a second then connects and breathes cyan. The Xenon resets, blinks green, then rapidly blinks green like it’s just about to connect to the cloud. The error I get is “your device could not connect to Device Cloud. Please try again”. I am using a an iMac 27" late 2013 with Mac OS Mojave, and I’m using the particle app on my iPhone 7S. The Xenon connected to the cloud when coupled to the Ethernet Featherwing, but then it’s acting as the gateway, and I want the Argon to act as the gateway, and the Xenon to connect to the Argon’s mesh network. My router is a Comcast Xfinity X1 router, where both 5G and 2.4G have the same network name and password, by Comcast default. I’ll try reflashing the Argon and using it with the featherwing ethernet adapter, which defeats the use of WiFi, but it’ll tell me if the wifi is the problem when I mesh it with the Xenon.

Xfinity router may be the problem.

Just to be clear, you are holding the setup button for three seconds to make it blink blue? I had a problem with this and realized I needed either a second xenon or I use the argon as a stepping stone into the mesh network. I ended up putting the argon in setup mode during the process to activate the xenon and it worked.

Yes, I followed the instructions and held the MODE button on the Argon so it would blink blue too. My problem turns out to be with the router. See my post above.