HELP: problem with HC-05 and relay

When I turn the programme on, the relay is always on and I cannot turn it off or on again. Can anyone help me out, what could be the problem.

I enclose the code.

#include <SoftwareSerial.h>
SoftwareSerial Bluetooth(0, 1);
int rel1=5;
int rel2=6;

char Data;

void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
Bluetooth.begin(9600);
pinMode(rel1,OUTPUT);
pinMode(rel2,OUTPUT);

}

void loop() {
// put your main code here, to run repeatedly

if(Bluetooth.available()){
Data=Bluetooth.read();
if(Data==('1')){
digitalWrite(rel1,HIGH);
}
if(Data==('2')){
digitalWrite(rel1,LOW);
}

if(Data==('3')){
digitalWrite(rel2,HIGH);
}
if(Data==('4')){
digitalWrite(rel2,LOW);
}
}
}

You are using software serial on hardware serial pins 0,1 - a certain route to disaster.. Since you do not intend to use serial monitor anyway, it is quite OK to use Bluetooth on pins 0,1 and use serial commands. Disconnect Bluetooth before you upload your programme. If you really want to use software serial, use other pins. As things are, you have no good reason to use software serial.

You might find the following background notes useful.