Zbt z8102ax bootloop

I tried to flash openwrt (both 23.05.5 an snapshot versions) on the router zbt z8102ax. I used the router webpage "ZBT MT7981 Uboot V2.0 FIRMWARE UPDATE
" to flash it. Now the router doesn't boot anymore. Any help? thanks

Which part of openwrt install is that?

https://git.openwrt.org/?p=openwrt/openwrt.git;a=commit;h=c8c2f522625c8d9eb5acad317e3de7a6b156decf

A. Through OpenWrt Dashboard:
If your router comes with OpenWrt preinstalled (modified by the seller),
you can easily upgrade by going to the dashboard (192.168.1.1) and then
navigate to System -> Backup/Flash firmware, then flash the firmware.

The seller installed a uboot dashboard (192.168.1.1): I uploaded the firmware .bin file, and than flashed.

Mayby there is something wrong with 8GB eMMC. Unfortunatelly I can't open the case to connect via UART.

Why you are asking here? You have not touched a single bit from openwrt.org
Ask seller to fix.

because since I flashed openwrt.org firmware and the router didn't boot anymore I was just asking some help. thanks anyway

Where in OpenWRT you have this?

I have no idea

Check here

thanks a lot for the tip