Medion E4272 laptop not working anymore?

For Christmas last year I got the Medion E4272 laptop. I have used it happily for 5 months but now it has not been working for 1 month.

I have already removed the battery and put it back in, hoping it was just a contact problem or something. Unfortunately, it didn't work.

No matter how often and for a long time I press the power button, the screen remains black and the 3 lights in the top corner remain off.

I desperately ask for a few ideas on how to fix this problem. Would not like to be a technician.

Battery out and only use with mains plug

Change button cell

Maybe your power supply is defective or test it without a battery

Button cell? What exactly does it mean?

Power plug means laptop charging cable?

Does the device beep when trying to switch it on? Otherwise, dust off the device, change the button cell or just try it with a power cable (remove the battery in front).

This battery that is also used in watches.

Exactly, but remove the battery beforehand

Ahh oh. Where exactly is it in the laptop?

That varies from laptop to laptop

No it makes no noise, let alone any signs of life. Because of the button cell, I would have another question. Do you have to buy them online? So does that have to be special for laptops? And where exactly do you put them in the laptop?

Warranty?

These are not special cells for the laptop, they are all identical (apart from the size). You can often find them in the supermarket. Before the laptop is unscrewed, you should be aware that this will invalidate the possible guarantee. On YouTube there are also some videos about the battery.