Help ! Troubleshooting error

Hi,

I create a simple program in arduino . The goal is that my mailbox send me a notification when the postman table a lettre.

But when i want to televerse the program, this error appear :

avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x86
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x18
avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0x18
avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0x86
avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x86
avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0x00
avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x18
avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0x1e
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x66
Une erreur est survenue lors du transfert du croquis

....

And this is my program

int LDR = 0;
int LDRvalue = 0; //definition for value of LDR at any given time
int maxlight = 300; //definiton for light limit before function if performed

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

void loop()
{
LDRvalue = analogRead(LDR);
{
if (LDRvalue > maxlight) //if the value the LDR is currently at is higher than the aximum light valure (pre-set at the top)...
{
delay (2000);
Serial.println("Tu as une lettre!");
}

}
}

So, can you help me and tell me what I have to do or what type of mistakes I made ?

Thank you !

( sorry for my bad English... )

I'm using a HC-05 Bluetooth module for sending the notifications *

Disconnect the bluetooth module while uploading code.