Only one motor is rotating

[StefanL38]

There is another thing that you should obey:

always post your complete sketch.

Your drive backwards function

@okers

void Backward()
{
digitalWrite(in1,HIGH); 
analogWrite(en1, 85);  // activate channel 1 which should belong to motor 1
digitalWrite(in3,HIGH);
analogWrite(en3, 85);  // activate channel 2 which should belong to motor 2
}

with this code-snippet it stays unclear what io-pin-numbers did you assign
en1 and en3

additional: why do you use en3 instead of en2?

@okers

i copied also all the diagram connection in to pin which is working..

this does not really say which IO-pins you use
these are all reasons why you should really
always post your complete sketch.

just a few mouse-clicks

You can insert your complete sketch as a code-section
which looks lke this

int Backward()
{

digitalWrite(in1,HIGH);
analogWrite(en1, 65); <----- not rotating..
digitalWrite(in2,LOW);
digitalWrite(in3,HIGH);
analogWrite(en3, 65);
digitalWrite(in4,LOW);
}
int Forward()
{
digitalWrite(in1,LOW);
digitalWrite(in2,HIGH);
analogWrite(en2, 65);
digitalWrite(in3,LOW);
digitalWrite(in4,HIGH);
analogWrite(en4, 65);
}

by following this tutorial

Make experienced users help: two ways to quickly post code as a code-section

Hi newcomer, This thread wants to show you how you can speed-up getting helpful answers with small effort. If you manage at least to post this way. You have the sympathy of the experienced users. If you are willing to invest another 20 minutes these 20 minutes extra-time will save you a minimum of 200 minutes to finish your project. always post your full sketch. As a code-section from the very first to the very last line A code-section has a small height => keeps your posting "short" but e…