diff --git a/Rust_State_Machine/en/Section_1/Lesson_4_Basic_Tests.md b/Rust_State_Machine/en/Section_1/Lesson_4_Basic_Tests.md
index 36826bc6..aaf6594e 100644
--- a/Rust_State_Machine/en/Section_1/Lesson_4_Basic_Tests.md
+++ b/Rust_State_Machine/en/Section_1/Lesson_4_Basic_Tests.md
@@ -33,10 +33,10 @@ For that, we will go back to the `main.rs` file, and create our first `#[test]`
 	fn init_balances() {
 		let mut balances = balances::Pallet::new();
 
-		assert_eq!(balances.balance("alice".to_string()), 0);
-		balances.set_balance("alice".to_string(), 100);
-		assert_eq!(balances.balance("alice".to_string()), 100);
-		assert_eq!(balances.balance("bob".to_string()), 0);
+		assert_eq!(balances.balance(&"alice".to_string()), 0);
+		balances.set_balance(&"alice".to_string(), 100);
+		assert_eq!(balances.balance(&"alice".to_string()), 100);
+		assert_eq!(balances.balance(&"bob".to_string()), 0);
 	}
 	```