Hi! I understand you're having trouble seeing lesson materials in the 51Talk AC (Active Classroom) even though your internet connection is stable. Let's work together to get this sorted out.

To help you better, may I ask:
- Are you using the 51Talk AC on your web browser or through an app?
- Have you tried refreshing or reloading the classroom page?
- Is the lesson material not loading at all, or do you see any error messages?

Meanwhile, here are some steps we can try to fix the issue:

1. Clear Browser Cache: Sometimes cached data can interfere with loading new content. On your Windows device with WebKit-based browser, try clearing the cache and then reload the AC.

2. Download and Drag Lesson Material: According to 51Talk FAQs, you can try downloading the lesson material file directly in the AC room, then drag the file into the lesson window to make it visible.

3. Check Browser Permissions: Ensure your browser settings allow pop-ups and content from 51Talk, as blocked pop-ups might prevent lesson material from appearing.

4. Verify Browser Compatibility: While using WebKit is generally supported, verify you're using an updated version of the browser, as outdated versions might struggle rendering content.

5. Try Another Browser: If possible, try accessing AC on a different browser like Chrome or Firefox to rule out browser-specific issues.

If you've already tried these or need more detailed guidance on any step, just let me know! We'll get your lesson materials showing up smoothly.

Are you satisfied with the solution I provided so far?