You are registered in Portugal. Which eBay site are you using?
ebay.com is not down, and has not been down for a while. You can check that yourself using a site like downdetector:
https://downdetector.com/status/ebay/
If you are unable to reach a particular page using a particular link, try another link or another page. Maybe your link is no longer redirecting properly.
Try another browser to rule out a browser issue.
Try another site to rule out a site issue.
Try another device to rule out a device issue.
Try another network to rule out a local network issue.
