Connected device not showing up

I read through a very long thread number of people complaining of devices connected to their WiFi but not showing up on the xfi app. I am currently having the same problem and it is an issue since I need to add port forwarding for that device. After reading the whole thread I was not able to find a solution. I have done everything I can think of to correct this issue but nothing has worked. Does anyone know how to fix this problem?

I have the tg1682g model and it's running with fw 3.14p15s1. Please help!