diff --git a/src/serve_data.js b/src/serve_data.js
index 75cc667..d9948e9 100644
--- a/src/serve_data.js
+++ b/src/serve_data.js
@@ -237,7 +237,13 @@ export const serve_data = {
           xy = [minX, minY];
         }
 
-        const fetchTile = await fetchTileData(source, sourceType, z, x, y);
+        const fetchTile = await fetchTileData(
+          source,
+          sourceType,
+          z,
+          xy[0],
+          xy[1],
+        );
         if (fetchTile == null) return res.status(204).send();
 
         let data = fetchTile.data;