My TP Link 3G router MR 3020 stucked after firmware update.

I have TP Link 3G router MR 3020 which I bought, It was not connecting via PTCL Evo 3G so I logged in to its admin page (192.168.0.254) and my friend told me to update it bin. after update and reboot it hung. Now neither it load admin page nor work. Its power light and reset button light remain on. Please guide me how to restore it to factory setting because I didn't even make backup of it nor know which version I updated it, just know the file name openwrt-ar71xx-generic-tl-mr3020-v1-squashfs-factory.
SOME BODY PLEASE HELP ME BECAUSE I AM A NEWBE