Server not found

The app might need additional configuration steps or some detail of the configuration is incorrect, or you’ve an incorrect DNS server setting, the DNS configuration that’s needed for this app is missing or wrong, or there’s an app bug. The latter two are largely out of your control. Somebody else deals with those, a d that effects more than one user of the app. The initial app login and setup configuration is something you’ll have to look at—I’m not familiar with the app. The DHCP problem is unlikely, but I’ve seen some folks that use “nanny” filters and that do hit these sorts of errors.

If the rest of your new iPhone is working and Safari can view other web pages, and if this same problem happens on a different Wi-Fi network, then this is probably the app.

Try a different Wi-Fi network. If it fails there, contact the support folks for the app vendor.

If this is for access to a school, contact the school folks for help (and not RenWeb), and also for whatever setup info might be needed for this app. If this is RenWeb for home, contact the RenWeb folks. https://www.renweb.com/Support/