The wifi on my child's iPhone 7 stopped working, so we got an iPhone SE to replace it. Now we want to erase the old phone, but we cannot turn off "Find My" because there is no apparent way to connect to an Apple server: no phone service because that's been transferred to the new phone, no wifi because wifi is broken on this phone. I can connect it directly to a Mac desktop, but the "Restore" option refuses to work without first disabling "Find My". We can try to disable "Find My" by going directly to iCloud.com/find, but of course the old phone doesn't know about this because it can't connect to anything.
So what do we do?
Maybe temporarily restore phone service to the old phone? How do we do that? Any other options?