I faced this exact issue a few weeks ago. Here are the most common reasons and fixes:

1. Check if cache is actually being restored

First, look at your workflow logs. Do you see Cache restored from key or Cache not found? If it says Cache not found, your key isn't matching.

Fix: Make sure package-lock.json exists and is being committed. If it's missing, hashFiles('**/package-lock.json') returns empty and cache misses every time.

2. Don't cache node_modules directly

The official docs actually recommend against caching node_modules. It can cause issues with Node version mismatches and npm ci.

Better approach: Cache ~/.npm instead:

- name: Cache npm dependencies
 uses: actions/cache@v4
 with:…