@Bart.P 

Hi,

Sorry to tell you that we only provide English Service for Global users, so we tried to translate your question into English and continue to help you. Wish your understanding.

If your router is no longer powering on, please confirm the below:

1. Check if you are using the original power adapter, try another one with the same spec to confirm if possible. 

2. Was there any power cut or bad weather or firmware upgrading before it behaves abnormally? 

3. Try to hard reset it by holding the reset button or hole for 10s.

4. When and where did you buy this also? If nothing can make it power on correctly, you may need to contact the local tech support to check the warranty cause the device seems faulty:
https://www.tp-link.com/en/support/contact-technical-support/#Hotline-Support

Have a good day.