Mini Smart Switch 1.3.10 Serial Flash

[chopin94]

Hi

I have bought 5 Mini Smart switch. 1.3.10 firmware.
I use arduino for usb to serial e two resistor for switch 5v to 3.3v serial.
I can read the firmware with ltchiptool on windows.

i do it:
connect
led turn on
cen to gnd and led blink
then i can read and save the firmware

when i try to flash the firmware, it send me an error message and the led don't turn on. if i connect 220v don't turn on anymore. Probably I have broken 3 of 5 LOL

W: Writing 4k failure @ 0x12000 (Chip CRC value 930734F8 does not match calculated CRC value 9661E050), retrying (attempt 0)
W: Writing 4k failure @ 0x12000 (No response received), retrying (attempt 1)
W: Erasing failure @ 0x12000 (No response received), retrying (attempt 0)

this is error

do you have any suggestion?