fresh start with MDBT42Q , some specs before start toe code

Ok, it's working - thank you!

but now I see another problem ,
when I try to read the pin status using this command:

NRF.setServices({
  "3e440001-f5bb-357d-719d-179272e4d4d9": {
    "3e440002-f5bb-357d-719d-179272e4d4d9": {
      description: "Setup Led",  // optional, default is null,
      writable : true,
      readable : true,
      notify: true,
      maxLen : 10,
      value : "Setup_Data",
      onWrite : function(evt) {
        data = evt.data[0];
        g.clear();
        g.setFontVector (20);
        g.drawString('Data receive',2,2);
        g.drawString(data,2,40);
        g.flip();
        if (data =="1") {
       // if (data < 18) {
           digitalWrite(LED, 1);
           digitalWrite(Relay_Pin, 1);
            }
       else {
       digitalWrite(LED, 0);
       digitalWrite(Relay_Pin, 0);}
       Relay_Status = digitalRead(Relay_Pin); 

      }
    },
	"3e440008-f5bb-357d-719d-179272e4d4d9": {
     description: "Device Temp",  // optional, default is null,
      readable : true,
      notify: true,
      value : [E.getTemperature()]
    }
  }
}, {});

it turn off the led that connected to Relay_Pin

when I remove the this line - the led stay on
what could be the problem ?
when I read the data from "nRF" I can see the value is "0x01"

and one final "understanding" question:
if I understand correct - there is no need for the connected device to know the Service UUID , just the CHAR uuid
there is no used of the service - right ?

***I mange to make my Python code work - and there I only used the CHAR UUID , didn't use \ took any attention for the Service UUID