diff --git a/src/freedombone-app-matrix b/src/freedombone-app-matrix
index c7247a83..399a0997 100755
--- a/src/freedombone-app-matrix
+++ b/src/freedombone-app-matrix
@@ -132,8 +132,8 @@ function matrix_nginx {
     fi
 
     if ! grep 'localhost:8448' /etc/nginx/sites-available/${DEFAULT_DOMAIN_NAME}; then
-        sed "s|:443 ssl;|:443 ssl;${matrix_proxy_str}|g" /etc/nginx/sites-available/${DEFAULT_DOMAIN_NAME}
-        sed "s| default_server;| default_server;${matrix_proxy_str}|g" /etc/nginx/sites-available/${DEFAULT_DOMAIN_NAME}
+        sed -i "s|:443 ssl;|:443 ssl;${matrix_proxy_str}|g" /etc/nginx/sites-available/${DEFAULT_DOMAIN_NAME}
+        sed -i "s| default_server;| default_server;${matrix_proxy_str}|g" /etc/nginx/sites-available/${DEFAULT_DOMAIN_NAME}
     fi
 
     systemctl restart nginx