Look on forums like Telecom-Cafe , DSLReports , or GuruHisp for your exact ISP + model. Example: “Movistar ZXHN H267N firmware update”.
: Ensure your computer or smartphone is connected to the router via Wi-Fi or an Ethernet cable. Open a browser : Enter the default IP address 192.168.1.1 in the address bar. : Use the default credentials (usually Update Software in ZTE ZXHN H267N