Unable to send report: plesk_mail() failed: Recipients list is empty.

[knocx]

Usage overgage Notification emails stopped coming so i run it manually from command line rather than cron


when i run this

/usr/local/psa/admin/bin/php /usr/local/psa/admin/plib/report/autoreport.php --auto daily

i get this error

Unable to send report: plesk_mail() failed: Recipients list is empty.

1- how can it become empty suddenly?
2- how can i fix this

knocx