diff --git a/bundles/org.smarthomej.binding.notificationsforfiretv/src/main/java/org/smarthomej/binding/notificationsforfiretv/internal/NotificationsForFireTVConnection.java b/bundles/org.smarthomej.binding.notificationsforfiretv/src/main/java/org/smarthomej/binding/notificationsforfiretv/internal/NotificationsForFireTVConnection.java
index 2bede8f999..970b8f5f6d 100644
--- a/bundles/org.smarthomej.binding.notificationsforfiretv/src/main/java/org/smarthomej/binding/notificationsforfiretv/internal/NotificationsForFireTVConnection.java
+++ b/bundles/org.smarthomej.binding.notificationsforfiretv/src/main/java/org/smarthomej/binding/notificationsforfiretv/internal/NotificationsForFireTVConnection.java
@@ -19,6 +19,7 @@
 import java.net.URI;
 import java.net.http.HttpClient;
 import java.net.http.HttpRequest;
+import java.net.http.HttpRequest.BodyPublisher;
 import java.net.http.HttpRequest.BodyPublishers;
 import java.net.http.HttpResponse;
 import java.net.http.HttpResponse.BodyHandlers;
@@ -103,9 +104,15 @@ public void addFilePart(String name, File file) throws IOException {
     public String send() throws IOException, InterruptedException {
         byteArrays.add(("--" + boundary + "--").getBytes(StandardCharsets.UTF_8));
 
+        int length = 0;
+        for (byte[] bytes : byteArrays) {
+            length += bytes.length;
+        }
+
+        BodyPublisher bodyPublisher = BodyPublishers.fromPublisher(BodyPublishers.ofByteArrays(byteArrays), length);
         HttpRequest httpRequest = HttpRequest.newBuilder()
-                .header("Content-Type", "multipart/form-data;boundary=" + boundary)
-                .POST(BodyPublishers.ofByteArrays(byteArrays)).uri(uri).build();
+                .header("Content-Type", "multipart/form-data;boundary=" + boundary).POST(bodyPublisher).uri(uri)
+                .build();
         HttpResponse<String> response = httpClient.send(httpRequest, BodyHandlers.ofString());
         if (response.statusCode() == HttpURLConnection.HTTP_OK) {
             return response.body();