Ever since upgrading to the above app version of xFi, I have been getting after logging into my account (providing ID/PW)... hourglassing followed by "Let's Try That Again... We couldn't load your settings. If the problem persisits, check back later." Included is a "Try Again" and "Sign Out" button... both result in same error message. I am on an iPhone 7 iOS version 11.2.5... I am getting same message/issue on iPad Mini 4th gen and iPad Pro 1st Gen... all running same iOS 11.2.5
And I assume you are on your home wifi SSID? Did you check?