xFi Pod compatibility with the XB6 Modem

I have the XFi modem/router (model XB6) and I've read online that the XFI Pod (Model B1A) are compatible. However, the Xfinity app doesn't allow me to connect the Pods with my system when I go through the setup & activation process. Why is the app not allowing me to connect compatible devices together? Are they not compatible? If not, why are there articles on the Xfinity site that says they are?