diff --git a/src/client_server/membership.rs b/src/client_server/membership.rs
index 732f616265c94c5417a07faaca0dba7a6eec154a..ec685ec9d378e3d408a8718f38259dfe0d1a36ac 100644
--- a/src/client_server/membership.rs
+++ b/src/client_server/membership.rs
@@ -934,7 +934,7 @@ pub(crate) async fn invite_helper<'a>(
                 unsigned.insert("prev_content".to_owned(), prev_pdu.content.clone());
                 unsigned.insert(
                     "prev_sender".to_owned(),
-                    serde_json::from_str(prev_pdu.sender.as_str()).expect("UserId is valid string"),
+                    to_raw_value(&prev_pdu.sender).expect("UserId is valid"),
                 );
             }
 
diff --git a/src/server_server.rs b/src/server_server.rs
index 68e262b4094d80f9c009cc1566bc33f23ff7f7de..482edf0f6a6935a607e6f61139a4881107abd1e9 100644
--- a/src/server_server.rs
+++ b/src/server_server.rs
@@ -2721,7 +2721,7 @@ pub fn create_join_event_template_route(
         unsigned.insert("prev_content".to_owned(), prev_pdu.content.clone());
         unsigned.insert(
             "prev_sender".to_owned(),
-            serde_json::from_str(prev_pdu.sender.as_str()).expect("UserId is valid string"),
+            to_raw_value(&prev_pdu.sender).expect("UserId is valid"),
         );
     }