What is the solution for 503 error when the server is up?

There is no CLI to download the snapshot.
Please try google drive or torrent on this page.
https://docs.creditcoin.org/updating-creditcoin-nodes#04db

I uploaded two snapshots of my server, which are more up-to-date and worked for me and other, but reportedly fail to work for SOFTK.
You can try them for your own sake. Torrent is available to download.