New Acer notebook no longer switches on?

I bought a notebook a few weeks ago, actually I wanted a PC, but I wanted to have a second one for important documents and so on, so that somehow a wrong program or something from the gaming computer would take my important documents apart.

Oh well. Now I've had it for 4 weeks and wanted to turn it on today to save a few documents, but it doesn't turn on anymore - only the fans are running and the keyboard lights come on - screen dark, no beeps or something.

It is an Acer S5-371

I have already tested the following:

Let the battery run empty, sometimes leave it without juice, then reconnect and start (since the battery can't be removed)
Start with Windows installation stick (original, but not part of the Lappi)
Start with the latest installation stick (freshly made with the Microsoft Tool)
Start with Ubuntu Live Stick
Every attempt to start only with the laptop screen and once with the HDMI monitor connected.

Unfortunately, no attempt did anything. Acer will accept the thing for repair, but then the data will be gone. I have a backup from a week ago, but it's still pretty stupid.

Does anyone have any ideas what I could try?

Have a look below you have a mini-hole with a symbol somewhere… This is the battery breaker… Simply press gently with a paper clip