Nighthawk

I purchased the R7960P last year and everything was working great until recently.  Now I can't get the Nighthawk App to connect to the router.  I can get in via a browser, but not the app.  Actually, I was able to connect once this evening...  I had to turn off Private Address in my WiFi settings of my phone.  Now it just keeps asking me to login.  No error message....  I keep trying and I eventually get a pop up saying "Logon timed out, please try again...."  I've deleted and re-installed the app, rebooted the router twice and double checked that it is running the latest version.  I've tried this on my iPhone and iPad with the same results.