Your iphone could not be activated because the activation server cannot be reached

Hi there!

1. Check the list on the System Status page. If the box by iOS Device Activation isn't green, try to activate your iPhone later.
2. If asked to enter your password as you activate your iPhone, enter the password. (A password prompt means that Activation Lock might be enabled in Find My iPhone.)
3. Restart your iPhone.
4. If you're using a cellular data connection, connect to a reliable Wi-Fi network instead.

If this doesn’t help, learn more things to try and how to activate via iTunes here: If you can't activate your iPhone - Apple Support or if you’d prefer to contact Apple Support, you can do so here: https://support.apple.com/