[AR750] new firmware 3.012 bricked my modem

i have installed new firmware gl-ar750-3.012-0111 on my AR750, now my router is bricked, i can’t acces by Webgui and by telnet ssh.
the ping is too slow, and after it not ping anymore.
how do i do for unbrick my router and why the new firmware not work ?

is it possible to unbrick my router with serial ttl ?

as soon as the router answered the ping I connected quickly and I put the update back and now it works.
I hope it’s going to hold on.

now my router configured as repeater disconnects and reconnect every 5 minutes alone, this is since the last version of the firmware.
sometimes it does not reconnect I have to do it manually. its a problem.

I delivered the old version and now everything works as before, against the last version of the firmware is very buggy, I hope he will do the necessary to make it more stable.

This is the guide about how to unbrick router

what is your old version number?