**Hello there! I'm an experienced tech expert. I'm sorry to hear you're having trouble approving your iPhone from another device using iOS 10. Here's a step-by-step guide to help you troubleshoot and resolve this issue:**

1. **Make sure both devices are connected to the same Wi-Fi network.**
2. **Sign in to the same Apple ID on both devices.**
3. **On the device you're approving, open the **Settings app and tap on [Your Name].

4. Tap on iCloud.

5. Tap on Sign Out.

6. Enter your Apple ID password and tap on Sign Out.
7.
Once you're signed out, tap on Sign In.
8.
Enter your Apple ID password and tap on Sign In.
9. **On the other device, you should now see a prompt to approve the sign-in.**
10.
Tap on Approve.

If you're still having trouble approving your iPhone from another device, you can try the following:

* Restart both devices.
* Reset your Apple ID password.
* **Contact Apple Support for further assistance.**

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Try these steps:Turn off iCloud Keychain on both the MacBook and iPhone.From your iPhone, go to Keychain and tap Approve with Security Code.When prompted for the 4-digit iCloud Security code tap Forgot Code.Follow the prompts to reset the code.Now this device should have iCloud Keychain enabled and working.More items...read more >>