I have a Nespresso Lattissima +, I just bought it and plugged it in. When I turn it on. All the four backlight buttons start flashing. What is wrong with it? How do I fix it? Thanks

This means there is no water flow. Add water to the tank. I am surprised the machine did not come with a user manual. You can download one below

on the bottom left side on/off switch

Lattissima Premium Silver EN 720

steam first in side milk *****

Your machine has almost certainly entered the water quality mode. (Water hardness setting). This is very easy to fix. Switch machine off. Before switching back on press and hold any off the following buttons: Latte Macchaito (top right) for soft water, Cappuccino (bottom right) for medium water or finally both of them for hard water. While holding the correct buttons switch the machine back on BUT hold for approx. 10 seconds or until all lights stop flashing, (APART FROM THE BUTTON YOUR HOLDING). This will reset the machine and you're good to go. Regards Coffee Engineer!

Take the water tank off and dry the bottom of it.

Hi. sounds like an ECU problem. Take to a repairer. Dazza REPAIRER

It means the machine is in Energy saving mode, that's it!

I had the same problem too.
Do repeat the descaling with water only. After the descaling the Lattissima shuts down. Just wait some time after shutdown before restarting the Lattissima again. The orange light will be turned off.
Hope this helps you too!

Have to pull out the entire container and push it back into the unit so it fully connects with the machine. Then try again.