Hey there, Rod! Thanks posting your question in the Apple Support Communities.
We understand that one device is unable to connect to this Wi-Fi hotspot. We know that staying connected is important and we can certainly help you research this issue.
To start, let’s be sure that you are following these instructions when connecting your wife’s iPhone 7 to this network: Connect to Wi-Fi on your iPhone, iPad, or iPod touch
If you’re still unable to get a solid connection after this, please try these troubleshooting steps: If your iPhone, iPad, or iPod touch won’t connect to a Wi-Fi network There are seven troubleshooting steps listed in this article, please be sure to complete all steps.
If you’re still unable to connect, can you tell us if the iPhone 7 is able to connect with other Wi-Fi networks normally?
Are your iOS devices and network router using the latest available system software? For help with updating your network hardware, contact the router's manufacturer. This Apple Support article explains how you can update your iPhone and iPad: Update your iPhone, iPad, or iPod touch
We hope this helps, cheers!