That message usually means that the Moodle server can't communicate with the Jobe (sandbox) server. If it was working before then I'd guess either the Jobe sandbox server or droplet stopped working or the networking/firewalling has changed and is now preventing the connection.
Some things to try:
- In the CodeRunner admin settings page, set the Jobe sandbox URL and API_Key back to their default values. Can you run questions now?
- From a command line try the following two bash commands:
wget --header="X-API-Key: 2AAA7A5415B4A9B394B54BF1D2E9D" jobe2.cosc.canterbury.ac.nz/jobe/index.php/restapi/languages
wget [yourjobeinaboxserverandport]/jobe/index.php/restapi/languages
Both should work. If neither work you have a networking problem. If the first works and the second doesn't, your jobe server is down.
Let us know what happens.
Richard