1. Are you running the query that uses the trigger in a transaction or have auto commit turned on?
2/ What is the setting for the consistency setting?
I'll have to verify the Auto Commit flag and consistency settings. I wouldn't know offhand how those are configured. I'll find that out shortly. I'm relatively new to MySQL though I'm quite familiar with MS SQL. As for the first question, I have a form in LibreOffice Base that updates the PackingListDetail table. When inserting new a record and saving it, the table trigger updates the CommodityNumber field correctly. However, when subsequently updating that same record in LibreOffice Base, the CommodityNumber field gets assigned a NULL value. There are no other table triggers that assign NULL values to this table. But if you update that record again in LibreOffice Base, the CommodityNumber field gets updated correctly. It oscillates back and forth between NULL and the correct value as that record is updated. I haven't confirmed if the behavior works the same if I run update and insert queries into the table from the MySQL Workbench. I should have done that first to rule out if LibreOffice Base is making some table calls that I can't currently see. I don't know if MySQL has a query analyzer type tool like MS SQL to allow you to see what SQL calls are being executed real-time against the MySQL server. I assume there is.
Please repost this problem on mysqlcommunity.slack.com and/or forums.mysql.com as the engineers actively monitor the posts. This is really odd situation.