I'm taking over administration of content for our local community website and am new to Drupal.  Unfortunately, his last newsletter issue is still showing as 'being sent by cron' 3 days later. A second message sent to subscribers also shows the same status. We previously had some delays with mass emailing (aprrox 750 subscribers) but the status then was showing as 'sent' and the newsletter arrived eventually up to 27 hours late.

Can anyone help me with solving this problem? Is it possible to cancel the offending newsletter issue and purge the system to clear any blockage, and how?

Grateful for any assistance!