LoRa.print() stopps working after first time if LoRa.sleep() is activated

[chmasi]

Dear All

This is my Code to send Lora Data ` void loop() {

//updateData();
sendLoraData();

for (int i = 0; i < 2; i++)
{
  LowPower.powerDown(SLEEP_8S, ADC_OFF, BOD_OFF);
}

}

void sendLoraData() {

LoRa.idle();
DBG_OUTPUT_PORT.print("Sending packet: ");
DBG_OUTPUT_PORT.println(counter);
//Send LoRa packet to receiver
LoRa.beginPacket();

LoRa.print('\0');   // Wrap update string
LoRa.print("<");
LoRa.print(myData.sensornr);LoRa.print(",");
LoRa.print(myData.temp);LoRa.print(",");
LoRa.print(myData.humi);LoRa.print(",");
LoRa.print(myData.pres);LoRa.print(",");
LoRa.print(myData.alti);LoRa.print(",");
LoRa.print(myData.vraw);LoRa.print(",");
LoRa.print(myData.airq);LoRa.print(",");
LoRa.print(myData.vcc);LoRa.print(",");
LoRa.print(myData.counter);
LoRa.print(">");

LoRa.endPacket();

//LoRa.sleep();

DBG_OUTPUT_PORT.println("data send finished");
DBG_OUTPUT_PORT.flush();
delay(100);

}`

This works quite fine,as soon I activate LoRa.sleep(), only the first time is working, after the second time it stops working and I have to manually reset the Arduino Pro Mini 3.3V 8 MHz

any suggestion how I can solve this issue?

[IoTThinks]

I believe the problem is how you make your MCU sleeps and wakes up. LowPower.powerDown(SLEEP_8S, ADC_OFF, BOD_OFF);

[chmasi]

I believe the problem is how you make your MCU sleeps and wakes up. LowPower.powerDown(SLEEP_8S, ADC_OFF, BOD_OFF);

I changed the code to delay(xxxx) instead of the LowPower.powerDown(SLEEP_8S, ADC_OFF, BOD_OFF) but result is the same after I put LoRa to sleep