Mi Router 4A Giga Edition OpenWrt -> Stock Firmware flash

My Mi Router 4A Giga Edition Router is running the latest Openwrt but I will have to send it back because the power connection has a lose contact and it loses power frequently. So before sending it back I will have to flash back the stock firmware. Does anyone know how to do that?

Download the correct Chinese or Global International firmware for your R4AG from Hoddy's Guide web page, found in link below.

Then use TinyPXE or the Xiaomi MiWFiRepairToolx86 to restore the firmware to the device.
https://openwrt.org/inbox/toh/xiaomi/xiaomi_mi_router_4a_gigabit_edition#debricking