Lora Ebyte E32 868Mhz Problem Leonardo

Hi I‘m from Germany so my English is not the best but never mind.
I bought 2 Lora Modules (Ebyte E32 868Mhz) and they work perfectly on the Arduino Uno but not on the Arduino Leonardo. I did not Receive anything?! I connected the Leonardo’s directly over the Arx and RX pins and it worked but not over the Lora? The Leonardo has Serial1 so I can connect the module to pin D0 and D1.
Here is my Sketch

void setup() {
Serial.begin(9600);
Serial1.begin(9600);
}

void loop() {
if(Serial.available()>0){
  String msg = Serial.readString();
  Serial1.print(msg);
  Serial.println(msg);
}
if(Serial1.available()>0){
  String msg = Serial1.readString();
  Serial.println(msg);
}
delay(20);
}

Here is the Link for the Manuel for the Module

http://www.ebyte.com/en/downpdf.aspx?id=132

And some useful Pictures
If someone have an Idee why it’s only working on the Arduino Uno, tell it me!

Sry here the Pictures

The device datasheet says 'For 5V TTL it may be a risk of burning down'

Are you connecting it to 5V TTL ?

srnet:
The device datasheet says 'For 5V TTL it may be a risk of burning down'

Are you connecting it to 5V TTL ?

Yeah I do, but it is allready working on the uno
How can I change it to 3.3 V?

Try a Google search on;

arduino 3.3v logic level conversion