Suddenly today morning started to get calls from learners that the course is not accessible. Checked Joomdle system check found out prntscr.com/lg5y6n
Joomla to Moodle HTTP connectivity Joomla cannot connect to Moodle
Moodle to Joomla HTTP connectivity Moodle cannot connect to Joomla
Joomdle Web Services Received empty response from Moodle
Checked the url in Joomdle, Moodle Admin->Users->Authentication->Manage Authentication->Joomdle auth plugin is enabled, Moodle Admin->Plugins->Enrolments->Manage enrol plugins->Joomdle auth plugin is enabled
It seems like maybe the server is not able to connect to itself, for some reason....well, not really, I tried to connect to it from here and I can't either, using a simple script with file_get_contents, no idea why.
Are you using file_get_contents or cURL? If using file_get_contents, you could try using cURL to see if that helps.
The administrator has disabled public write access.