diff --git a/ubuntu/mastodon.zombocloud.com.yml b/ubuntu/mastodon.zombocloud.com.yml
index d4514f7..870e028 100644
--- a/ubuntu/mastodon.zombocloud.com.yml
+++ b/ubuntu/mastodon.zombocloud.com.yml
@@ -25,8 +25,8 @@
         - error_log "/var/log/nginx/mastodon.zombocloud.com.error.log"
         - ssl_certificate "/etc/ssl/letsencrypt/mastodon.zombocloud.com.crt"
         - ssl_certificate_key "/etc/ssl/letsencrypt/mastodon.zombocloud.com.pem"
-        - add_header Strict-Transport-Security max-age=31536000; includeSubDomains
-        - add_header Referrer-Policy no-referrer, strict-origin-when-cross-origin
+        - add_header Strict-Transport-Security "max-age=31536000; includeSubDomains"
+        - add_header Referrer-Policy "no-referrer, strict-origin-when-cross-origin"
         - location / {
             try_files $uri @proxy;
           }
@@ -50,8 +50,8 @@
             proxy_cache_valid 200 7d;
             proxy_cache_use_stale error timeout updating http_500 http_502 http_503 http_504;
             add_header X-Cached $upstream_cache_status;
-            add_header Strict-Transport-Security max-age=31536000; includeSubDomains;
-            add_header Referrer-Policy no-referrer, strict-origin-when-cross-origin;
+            add_header Strict-Transport-Security "max-age=31536000; includeSubDomains";
+            add_header Referrer-Policy "no-referrer, strict-origin-when-cross-origin";
             tcp_nodelay on;
           }
         - location /api/v1/streaming {