Nginx response buffering issue

it's weird, as files being buffered are less than 100kb and the network is fast on the client side.

log:

[warn] 9#9: *10937 an upstream response is buffered to a temporary file /var/cache/nginx/proxy_temp/5/09/0000000095 while reading upstream, client: <IP ADDRESS>, server: gecom.alexdeathway.me, request: "GET /static/fonts/fontawesome6/webfonts/fa-solid-900.woff2 HTTP/1.1", upstream: "http://<SERVER IP>/static/fonts/fontawesome6/webfonts/fa-solid-900.woff2", host: "gecom.alexdeathway.me", referrer: "https://gecom.alexdeathway.me/static/fonts/fontawesome6/css/solid.css"