Bricked ZBT Z5001AX router

I tried to flashing it but it takes very long time about 2-3 hours.
I reckon I bricked it.

makes you wonder what you flashed it with, since it's not supported...

Chinese sent it to me with OpenWrT

doesn't really answer the question though.

unsupport/ed/able/ devices will also ship with openwrt, it doesn't say anything about their portability.

Is any possibility of recovering and use it again?

probably, but you need to find a fw for it, at ZBT, as a start.

Yes.
I download fw from them, but I bricked it.

oh!

you should ask ZBT.

you could try to initiate the recovery as described in https://git.openwrt.org/?p=openwrt/openwrt.git;a=commit;h=046263095e007ba80bdf3525de32d7cce11734e8

you will still need the correct image, the one you've got doesn't seem to be the right one, since it bricked your device.

Firmware is OpenWrt Chaos Calmer 15.05.1 23.0608_1.
I thought it will be easy to make it works with SIM card.
Then I tried with that firmware.