Cox Wifi App and Port Forwarding

What is going on with the Cox wifi app and port forward? It's already annoying that port 80 is blocked and I have to spend all day figuring out other solutions. When you log into the router/modem and view connected devices it shows old hostnames. When you want to port forward you have to use the cox wifi app which shows old internal ips. You can configure a port forward but it shows "No connected devices". Of course it does because there is no device on my network with internal ip ending in .177. There is also no device with hostname DESKTOP-LNCU008 and hasn't been for almost 24 hours. 

Never in my 25 years of computer usage has port forwarding been such a task. Fix this. 

I just install a fresh copy of ubuntu server on a desktop. Why is there still a device called "lenovo" listed in the app with an IP that isn't associated with any device on my network? Clearly the information does not get updated properly.