XB8-T port forwarding function never works on my app

Hello KJChicago was this a port forward that you already had set up?  When using the following navigation details, is this already active? 

In the Xfinity app, navigate to Wi-Fi > View Wi-Fi equipment > Advanced settings > Port forwarding.

@KJChicago @XfinityBradM 

Please circle back here and post any possible solutions for the issue here in these open public forums so that all readers here may benefit from the exchange / info. This is in keeping with the spirit for which these public help forums were originally intended. Thank you.

Update:

If you don't have time to read the lengthy report, just read the bold lines. that is one makes mine working. though nobody knows why it went that way and nobody can predict if it will not be changed due to some other irrelvent changes. 

Day 1:

Was able to get some response by using direct message method. but their response is slow, ususally takes 30 mins to an hour to get a response to your input. So after like 20 hours, they are still trying to understand the situation. 

From my side, I played around the app, and tried to change my DHCP server starting address from original x.x.x.2 to x.x.x.100. Now I can pass the page that has been giving me an error for years!!! So now, I can add port forwarding rules now. This is good part.

The bad part is, the port forwarding always point to a WRONG IP -- always to .100 -- the starting IP of DHCP. I then tried to change the DHCP starting IP back to .2. I can still pass port forwarding page that gave me errors for years, but always ended up with .100 as the reserved IP. Somehow the router (XB8) keeps thinking my NAS using x.x.x.100 as the ip, but in fact my NAS has been using x.x.x.5 for ever!

Searched around in this forum, and found many people reporting this issue and no solution is provided. almost all posts ended with a 'Direct Message" method. So I guess and hope they can solve it with some advanced support?

Day 2:

The support asked many questions, including to provide the screenshot of the Device List on the app, as well as the screen shot on the Reserved IP by login into XB8 directly. Both sites confirmed that my NAS has .5 address, and has never been set to .100 address. then they suggest I disconnect all the other devices except my NAS and try to setup again -- a bit ridiculus ha? cause I assume at least I should have my phone connected to run the app! well, I tried my best to disconnect everything exccept my phone (via wireliess) and my NAS (wired to Modem), still the same thing. 

After this I ran up my patience -- all the changes I tried above is paired with a restart of the modem to make sure it takes -- too many compliants from family members! I just chose to assign my NAS .100 address. and now it works. However, a lot of other configurations for my other service needs modify. All the related apps on phones, tablets, and TVs, fire TVs, as well as some control app on my NAS need to update. 

My journey is over. Will not update.  

@KJChicago 

Thanks for updating your topic ! Hope you get a final solution ! Best of luck with it !