Cloudflare Dynamic Content Purging: Why Are My Updates Not Live?

I'm tearing my hair out trying to get Cloudflare's dynamic content purging to work for my SaaS. Our users are seeing stale data, and I'm completely stuck!

• Context: We have a dashboard with frequently updated user data and analytics. When a user makes a change or new data comes in, we need that reflected immediately. We're using Cloudflare for performance, but this cache issue is killing us.
• Problem: Even after triggering cache purges, users often see old data for several minutes, sometimes longer. It's like the real-time content updates we need just aren't happening reliably.
• What I've Tried:
  • Using Cloudflare's Purge by URL (single and multiple) via API.
  • Purging Everything via API (as a last resort, which is terrible for performance).
  • Setting Cache-Control: no-cache, must-revalidate on relevant API endpoints (though Cloudflare still seems to cache it).
  • Checked Page Rules – nothing seems to be overriding the cache control.
  • Verified origin server is sending correct ETag and Last-Modified headers.
• Example of Failure (Dummy Error Log/Console Output):

  // User A updates their profile.
  // API purge for "/api/user/A/profile" is triggered.
  // User A refreshes browser.
  // Network tab shows:
  // Request URL: https://mysaas.com/api/user/A/profile
  // Status: 200 OK (from Cloudflare cache)
  // CF-Cache-Status: HIT
  // Age: 120 // (Shows 2 minutes old content!)
  // Expected: CF-Cache-Status: DYNAMIC or MISS, Age: 0

• My Question: What am I missing? Is there a specific header or Cloudflare setting that guarantees immediate cache invalidation for dynamic content?