Update Zte Router Firmware |link| -

Do not perform a firmware update over Wi-Fi. If the Wi-Fi signal drops during the 2-minute upload window, the update fails. Use an Ethernet cable to connect your laptop directly to one of the LAN ports on the ZTE router.

Let’s simulate the process for the popular ZTE ZXHN H298A: Update Zte Router Firmware

A: Your ISP is blocking the update. They test firmware extensively before release. You must wait for them to authorize it. Do not perform a firmware update over Wi-Fi