Amazon’s Echo gadgets are easy to use and one of the convenient features is that they update themselves automatically whenever new software is available, so you're always using the latest version with all the new features and security updates.
You can check which version your Echo is running by opening the Alexa app on your phone (or by going to alexa.amazon.com in your web browser). If you have an Echo Show, you can swipe down from the top of the screen, tap Settings then Device Options and Check for Software Updates.
In the Alexa app, tap the three horizontal lines in the top-left corner (or swipe right) and then tap Settings > Device settings.
Tap on the Echo you want to check and scroll to the bottom. Tap on About and your will see the Device Software Version listed.
How to force your Echo to update
If you’re expecting a new feature from a software update, typically your Echo will automatically download and install the update overnight.
But you can force an update by pressing the microphone mute button. The light ring will turn red (it's a red line on the display of an Echo Show), and the Mute button will also glow red.
Now, it's just a case of waiting. After a few minutes, assuming there is a newer version available, your Echo should announce that it needs to update and will restart once that’s complete.
This can take anywhere between a few minutes and an hour, so leave the mic muted and wait.
When it restarts, you can check the app again, where you should find the software version has changed.
An alternative method which has worked for some people, is to unplug the mains power supply, wait a few seconds, then plug it back in. Press the Mute button and when the Echo re-connects to Wi-Fi it will detect the new software, announce that it is going to install it and restart.