To help find the exact solution for your router, let me know:
If the standard browser update fails, some users report success by resetting the router and using the default IP in a fresh browser session to access the emergency upload page. ZTE ZXHN H108L with firmware 4.0.0d_ZRQ_GR4 ... - GitHub zxhn h108l firmware
Complete Guide to ZXHN H108L Firmware: Updates, Configuration, and Troubleshooting To help find the exact solution for your
Firmware is tailored to this BCM63xx reference design. zxhn h108l firmware