fix

counter/src/lib.rs

@@ -26,7 +26,6 @@ pub fn process_instruction(
     instruction_data: &[u8],
 ) -> ProgramResult {
     let (instruction_discriminant, instruction_data_inner) = instruction_data.split_at(1);
-    set_return_data(instruction_discriminant);
     match instruction_discriminant[0] {
         1 => {
             msg!("Instruction: Increment");
@@ -55,7 +54,7 @@ pub fn process_increment_counter(
     let mut counter = Counter::try_from_slice(&counter_account.try_borrow_mut_data()?)?;
     counter.count += 1;
     counter.serialize(&mut *counter_account.data.borrow_mut())?;
-
+    set_return_data(&counter.count.to_le_bytes());
     msg!("Counter state incremented to {:?}", counter.count);
     Ok(())
 }