MKS TinyBee problem

[krzychu521]

Hello
I have a problem with MKS TinyBee board.
I used grblhal web builder to create firmware.
Next using OpenBuild Control software i flashed board using downloaded firmware.
And it worked. Openbuild cobtrol, Universal gcode sender, gsender connect to board, and i can send $ codes to board.
Inverted using $14 inputs for Estop, and etc.
After that i connected four drivers and stepper motors. And i worked.
So i turn off and disconnected drivers from board.
When i was trying connect PC to board again, i cannot do that.
PC see the board, gsenders also see the board, but cannot connect to that.
I tried flash board again using the same method, but this time it not work. Openbuild control says:

A fatal error occurred: Failed to connect to ESP32: Timed out waiting for packet header : Make sure the device is in BOOTLOADER MODE. Your computer failed to put it into Bootloader mode automatically. You can enter bootloader mode by: Press and hold down MODE, then Press RESET while still holding MODE. Let go of RESET, then wait a second or two and let go of MODE. Best performed right after starting the Firmware Flashing operation.

But how?
On MKS TinyBee board red and white led are turn on, cpu is quite hot.
When trying firmware upgrade blue led is blinking on board.
I also try to use Flash Download Tool from grlhal link, but also not worked.

Any ideas?
Board is burnt out?
Or something else.
There is a white push button on board. I have no idea function of this. I think that it is reset, but not worked
Thanks for help

[terjeio]

It is a fair chance the MCU has been damaged. It can get pretty warm but should not be burning hot.