Magento – Cron job error SQLSTATE[40001]: Serialization failure: 1213 Deadlock found when trying to get lock

Suddenly and without reason, I get error via the mail concerns a cron job that could not be executed.

Here is the report :

*[Magento\Framework\DB\Adapter\DeadlockException]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
  SQLSTATE[40001]: Serialization failure: 1213 Deadlock found when trying to get lock; try restarting transaction, query was: DELETE FROM `yjuk_cron_schedule` WHERE (status = 'pending') AND (job_code in ('ddg_automation_customer_subscriber_guest_sync', 'ddg_automation_importer', 'ddg_automation_status', 'ddg_automation_abandonedcarts', 'ddg_automation_reviews_and_wishlist', 'ddg_automation_campaign', 'ddg_automation_order_sync', 'ddg_automation_cleaner', 'ddg_automation_catalog_sync', 'ddg_automation_email_templates')) AND (created_at < '2018-08-14 12:03:03')  
  [Zend_Db_Statement_Exception]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        

SQLSTATE[40001]: Serialization failure: 1213 Deadlock found when trying to get lock; try restarting transaction, query was: DELETE FROM `yjuk_cron_schedule` WHERE (status = 'pending') AND (job_code in ('ddg_automation_customer_subscriber_guest_sync', 'ddg_automation_importer', 'ddg_automation_status', 'ddg_automation_abandonedcarts', 'ddg_automation_reviews_and_wishlist', 'ddg_automation_campaign', 'ddg_automation_order_sync', 'ddg_automation_cleaner', 'ddg_automation_catalog_sync', 'ddg_automation_email_templates')) AND (created_at < '2018-08-14 12:03:03')  
  [PDOException]                                                                                                   
  SQLSTATE[40001]: Serialization failure: 1213 Deadlock found when trying to get lock; try restarting transaction  
cron:run [--group GROUP] [--bootstrap BOOTSTRAP]*

Do you know why? And how can I solve it?