diff --git a/src/main/java/com/epam/aidial/core/util/BufferingReadStream.java b/src/main/java/com/epam/aidial/core/util/BufferingReadStream.java
index 4e84a868c..ee7421215 100644
--- a/src/main/java/com/epam/aidial/core/util/BufferingReadStream.java
+++ b/src/main/java/com/epam/aidial/core/util/BufferingReadStream.java
@@ -143,18 +143,21 @@ private synchronized void handleChunk(Buffer chunk) {
         }
         if (eventStreamParser != null) {
             // build chain of chunk futures: the chunks should be sent in the same order as they arrive
-            Future<Boolean> future = eventStreamParser.parse(chunk)
-                    .andThen(result -> handleStreamEvent(chunk, result.result() == Boolean.TRUE, pos));
             if (streamHandlerFuture == null) {
-                streamHandlerFuture = future;
+                streamHandlerFuture = parseChunk(chunk, pos);
             } else {
-                streamHandlerFuture = streamHandlerFuture.transform(result -> future);
+                streamHandlerFuture = streamHandlerFuture.transform(ignore -> parseChunk(chunk, pos));
             }
         } else {
             notifyOnChunk(chunk);
         }
     }
 
+    private synchronized Future<Boolean> parseChunk(Buffer chunk, int pos) {
+        return eventStreamParser.parse(chunk)
+                .andThen(result -> handleStreamEvent(chunk, result.result() == Boolean.TRUE, pos));
+    }
+
     private synchronized void handleStreamEvent(Buffer chunk, boolean isLastChunk, int pos) {
         if (isLastChunk) {
             if (lastChunkPos == -1) {
diff --git a/src/main/java/com/epam/aidial/core/util/EventStreamParser.java b/src/main/java/com/epam/aidial/core/util/EventStreamParser.java
index 384b709de..bc4a01cd4 100644
--- a/src/main/java/com/epam/aidial/core/util/EventStreamParser.java
+++ b/src/main/java/com/epam/aidial/core/util/EventStreamParser.java
@@ -85,7 +85,8 @@ public synchronized Future<Boolean> parse(Buffer chunk) {
         if (futures == null) {
             return Future.succeededFuture(lastChunk);
         }
-        return Future.join(futures).transform(ignore -> Future.succeededFuture(lastChunk));
+        boolean localLastChunk = lastChunk;
+        return Future.join(futures).transform(ignore -> Future.succeededFuture(localLastChunk));
     }
 
     private void handleEventStage(Buffer chunk) {