diff --git a/src/Oh.My.Stitcher/Program.cs b/src/Oh.My.Stitcher/Program.cs
index cc76777..b14c5c5 100644
--- a/src/Oh.My.Stitcher/Program.cs
+++ b/src/Oh.My.Stitcher/Program.cs
@@ -67,8 +67,6 @@ app.MapPost("/api/image/generate", (Stitch request, IMemoryCache cache) =>
             if( value is string path )
               File.Delete(path);
           });
-        logger.ZLogDebug($"save cache key: {cacheKey}, file: {newCacheFile}");
-        cache.Set(cacheKey!, newCacheFile, cacheEntryOptions);
 
         await using FileStream cacheStream = new(newCacheFile, FileMode.Create, FileAccess.Write, FileShare.Read);
         while( true )
@@ -83,8 +81,11 @@ app.MapPost("/api/image/generate", (Stitch request, IMemoryCache cache) =>
           if( result.IsCompleted )
             break;
         }
+        logger.ZLogDebug($"save cache key: {cacheKey}, file: {newCacheFile}");
+        cache.Set(cacheKey, newCacheFile, cacheEntryOptions);
       });
       image?.WriteToStream(innerPipe.Writer.AsStream(), ".png");
+      await innerPipe.Writer.CompleteAsync();
     }
     catch( Exception e )
     {