diff --git a/dust-lang/src/instruction/mod.rs b/dust-lang/src/instruction/mod.rs
index a50ba9b..8e130d7 100644
--- a/dust-lang/src/instruction/mod.rs
+++ b/dust-lang/src/instruction/mod.rs
@@ -787,7 +787,7 @@ mod tests {
             TypeCode::CHARACTER,
         );
 
-        assert!(instruction.d_field());
+        assert!(!instruction.d_field());
     }
 
     #[test]