Lora did not send data if ESP32 Serial not connected to PC

hello, im using lora E32 1 watt. i have problem with my LoRa which the transmitter wont send the data if the ESP32 Serial0 did not connected to PC first, so when I turn on the ESP32 with PSU or USB Power(without connecting serial) the LoRa did not sent the data but after I connect the USB to PC and power it with PSU then unplug the USB serial it still work.