M_NOT_YET_UPLOAD and can not override,and change the result asyncupload to pass

src/core/error/response.rs

@@ -60,6 +60,9 @@ pub(super) fn bad_request_code(kind: &ErrorKind) -> StatusCode {
 		// 429
 		| LimitExceeded { .. } => StatusCode::TOO_MANY_REQUESTS,
 
+		// 409
+		| CannotOverwriteMedia => StatusCode::CONFLICT,
+
 		// 413
 		| TooLarge => StatusCode::PAYLOAD_TOO_LARGE,
 
@@ -69,6 +72,9 @@ pub(super) fn bad_request_code(kind: &ErrorKind) -> StatusCode {
 		// 404
 		| NotFound | NotImplemented | FeatureDisabled => StatusCode::NOT_FOUND,
 
+		// 504
+		| NotYetUploaded => StatusCode::GATEWAY_TIMEOUT,
+
 		// 403
 		| GuestAccessForbidden
 		| ThreepidAuthFailed

src/service/media/mod.rs

@@ -159,6 +159,10 @@ impl Service {
 	) -> Result<()> {
 		let pending = self.db.search_pending_mxc(mxc).await;
 		let Some((owner_id, expires_at)) = pending else {
+			if self.get_metadata(mxc).await.is_some() {
+				return Err!(Request(CannotOverwriteMedia("Media ID already has content")));
+			}
+
 			return Err!(Request(NotFound("Media not found")));
 		};