GL-S1300 return to GL firmware from

Hello, I have a S1300 with openwrt, I would like to go back to GL firmware, but after flashing it via uboot, it restarts and is still with openwrt firmware,
I flashed the last version from here(3.215): GL.iNet download center

Please try it.
http://download.gl-inet.com.s3.amazonaws.com/firmware/s1300/for_vanilla_openwrt/norplusemmc-ipq40xx-single.img

Do I install it from uboot or web interface of openwrt?

You should use Uboot.