[db_error: message="DB Error: connect failed" code=-24 mode=callback callback=CRM_Core_Error::handle prefix="" info=" [nativecode=Access denied for user 'xxxxxx'@'localhost' (using password: YES)]"]

Looks like you don't have the correct username and / or password for your CiviCRM database in the CiviCRM Database setting (civicrm.settings.php): CIVICRM_DSN.

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