Is this a NodeJS project? A fix has been released, you just have to update your node version to 24.18.0 or newer

Two known causes produce this exact symptom right now — check which one you have:

1. Node.js regression (nodejs/node#63989): ERR_STREAM_PREMATURE_CLOSE on keep-alive

   socket reuse was introduced in Node v24.17.0. If your build resolved to 24.17.0

   (e.g. engines.node "24" or "24.x" floats to latest = 24.17.0), that's likely it.

   Check your live Node version, not what you think you pinned. Fix: pin the EXACT

   patch to 24.15.0 or 24.16.0 (pre-regression) — a bare major re-resolves to 24.17.0.

   On Railpack: engines.node "24.15.0" + set RAILPACK_NODE_VERSION=24.15.0.

   Tell: it's deterministic (fails 100% from deploy), not tied to a clock time.

2. Transient egress/network incident: if it STARTED at a specific time (you said

   ~21:40 BRT) and worked before, and other egress is fine, this may be a platform

   edge/egress incident rather than Node. Check the status page for an active

   incident in your region. Tell: sudden onset at a timestamp, was working earlier.

Your "started ~21:40" detail leans toward #2, but confirm your live Node version

first (curl your own /health or log process.version) — if it's 24.17.0, rule out

#1 by pinning to 24.15.0 regardless. That's a 5-min test and it's free to rule out.