When mandatory custom fields were added to a DocType (i.e. Sales Invoice), existing auto repeats will naturally fail because that field is empty.
To fix this (mysqldump first!):
cd /var/www/frappe-bench (or wherever yours is) bench --site erp.km-it.de mariadb SET SQL_SAFE_UPDATES = 0; UPDATE `tabAuto Repeat` a INNER JOIN `tabSales Invoice` b on a.reference_document = b.name SET b.custom_description = a.frequency; SET SQL_SAFE_UPDATES = 1;
(here custom field is “description” and is set to auto repeat frequency)