Check if the website is really down, use a 3rd party service like: https://downforeveryoneorjustme.com

Check where the domain is hosted, see https://docs.brightvessel.com/docs/where-is-a-domain-hosted/

If the domain is not found on the tool, it might not be hosted by us, check it’s IP. If the IP belongs to one of our servers, contact Mihai to add it.