Apple Watch can’t download last update

Did you already try the troubleshooting mentioned in the related article?

...

Try these steps:

1. Make sure that your Apple Watch is connecting properly to its charger. 
2. Restart your Apple Watch.
3. Restart your paired iPhone.
4. Try again to update your Apple Watch.

If the update won't start:

1. Open the Apple Watch app on your iPhone.
2. Tap General > Storage.
3. Delete the update file.
4. Try again to update your Apple Watch.

...

copied from: Update your Apple Watch - Apple Support

There are a few things to do before you update your Apple Watch, did you make sure.. ⇢

• Your iPhone is updated to the latest version of iOS.
• Your Apple Watch is at least 50 percent charged.
• Your iPhone is connected to Wi-Fi.

The most recent WatchOS is 10.6.1.

Learn how to ⇢ Update your Apple Watch - Apple Support

-Zachyy ✌️

neftali161 wrote:

I try downloading the last update failed

What happened when you tried?

neftali161 wrote:

I try downloading the last update failed

Any kind of message?