Any idea what is the cause of this error & how to fix this?
[INSERT INTO `ostjobs_thread_referral` SET `thread_id` = 122117, `object_id` = 34, `object_type` = 'D', `created` = NOW()]
Duplicate entry '34-D-122117' for key 'ref'<br />
<br />
---- Backtrace ----<br />
#0 (root)/include/mysqli.php(207): osTicket->logDBError()<br />
#1 (root)/include/class.orm.php(3482): db_query()<br />
#2 (root)/include/class.orm.php(658): MySqlExecutor->execute()<br />
#3 (root)/include/class.thread.php(1961): VerySimpleModel->save()<br />
#4 (root)/include/class.thread.php(380): ThreadReferral::create()<br />
#5 (root)/include/class.ticket.php(3039): Thread->refer()<br />
#6 (root)/include/class.thread.php(1418): Ticket->systemReferral()<br />
#7 (root)/include/class.mailfetch.php(880): ThreadEntry::lookupByEmailHeaders()<br />
#8 (root)/include/class.mailfetch.php(955): MailFetcher->createTicket()<br />
#9 (root)/include/class.mailfetch.php(1035): MailFetcher->fetchEmails()<br />
#10 (root)/include/class.cron.php(25): MailFetcher::run()<br />
#11 (root)/include/class.cron.php(111): Cron::MailFetcher()<br />
#12 (root)/include/api.cron.php(19): Cron::run()<br />
#13 (root)/include/api.cron.php(40): CronApiController->run()<br />
#14 (root)/api/cron.php(23): LocalCronApiController::call()<br />
#15 {main}
Thanks