Zl-cpe5g Firmware |link| Direct

: Stock firmware handles 4G+5G NSA (Non-Standalone) well but can be aggressive in switching back to LTE to save power.

printenv bootargs=console=ttyS0,115200 root=/dev/mtdblock5 rw bootcmd=nboot kernel; bootm Zl-cpe5g Firmware

This usually happens due to a corrupted download or trying to install firmware meant for a different hardware revision. Double-check the hardware version on the bottom sticker of your router. : Stock firmware handles 4G+5G NSA (Non-Standalone) well