Go to .
ISPs rarely push the latest ZTE firmware. While "flashing" a generic ZTE firmware can fully unlock the device, . Flashing the wrong firmware can "brick" the device (render it useless) or break your internet connection (VOIP/IPTV settings). unlock zte f670l better
Switch to Google (8.8.8.8) or Cloudflare (1.1.1.1) for faster browsing. unlock zte f670l better
Go to Application > UPnP and enable it. This helps consoles like PS5 or Xbox achieve an "Open NAT" type. unlock zte f670l better