Hi all,
When you submit to the current challenge, you should be getting progress e-mails. However if your team settings are not set to:
"any synapse user can email this team"
These will not get to you. I strongly recommend changing your settings to this, or you won't be able to debug any errors you might be getting.
@miro-beda You are currently making submissions that are cauisng this error. Please do as described above.