Diagnostics of sync2em account not working

I added sync2em account for task and calendar synchronisation. The account was added, works (synchs) most of the time; but by whiles I get errors. I wanted to do a diagnostic check of the synch2me account, but the field "diagnose cannot be clicked; see:
In my other (gmail) accounts, the “diagnose” button can be clicked and works perfectly.

The diagnostics can be used just for the email accounts. If you experience difficulties just activate diagnostics logs for sync2em’s CalDAV and send them to us.

OK, loud and clear.
I have frequent hicups with the sync2em CalDAV. To which e-mail address can I send the logs for analysis?

Send it to [email protected] Thank you.