I just found this.

[19-Apr-2019 10:55:02 UTC] PHP Fatal error:  Uncaught Error: Call to undefined method BxDolAccount::getLanguageId() in /home/xxxxx/public_html/modules/boonex/notifications/classes/BxNtfsModule.php:435
Stack trace:
#0 /home/xxxxx/public_html/modules/boonex/notifications/classes/BxNtfsCronQueue.php(37): BxNtfsModule->sendNotificationPush(Object(BxDolProfile), Array)
#1 /home/xxxxxx/public_html/periodic/cron.php(117): BxNtfsCronQueue->processing()
#2 /home/xxxxx/public_html/periodic/cron.php(149): runJob(Array)
#3 {main}
  thrown in /home/xxxxx/public_html/modules/boonex/notifications/classes/BxNtfsModule.php on line 435