diff --git a/nginx.conf b/nginx.conf
index 01ef84d..4208db4 100644
--- a/nginx.conf
+++ b/nginx.conf
@@ -73,6 +73,8 @@ http {
       listen 80 http2;
       server_name api.flowy.live;
 
+      default_type application/grpc;
+
       location / {
         # Replace localhost:50051 with the address and port of your gRPC server
         # The 'grpc://' prefix is optional; unencrypted gRPC is the default
@@ -84,6 +86,8 @@ http {
       listen 443 ssl http2;
       server_name api.flowy.live;
 
+      default_type application/grpc;
+
       # RSA certificate
       ssl_certificate /etc/letsencrypt/live/flowy.live/fullchain.pem; # managed by Certbot
       ssl_certificate_key /etc/letsencrypt/live/flowy.live/privkey.pem; # managed by Certbot