What pin did you use for RX?
I used pin 3, as it is shown in schematics.
Another question. When i used HardwareSerial Serial2(1) instead of the working TX, i got the led blinking. Which is strange because the onboard led isnt pin 1, but pin 2. If i used HardwareSerial Serial2(0) i got the tx working as intended. Which is strange because pin 0 doesnt even exist in the schematics.