Upload issue while Build is ok

[valentinmagdelenne-beep]

Hello,

I have used the proposed programm . Build is ok but upload doesn't work.
the only error : A fatal error occurred: Failed to connect to ESP32: No serial data received.

device check ok
clean ok
build ok
the ESP32 is connected by a cable
ther's already the program loaded into the ESP32dev board. it was loaded by another person.
the server works
i can see the device on the WIFI network.

any idea ?
sorry i am learning. probably sth obvious to do :('

[pki791]

Put the ESP into bootloader mode by pressing and holding the boot button during power on.