PDF export does not work anymore after migration to MySQL

I created an AppSheet app using google sheets as database. I migrated the app to a MySQL database on my own VPS using this instruction

I tested the migrated app and everything seems to work fine, except that there is an issue with the workflow which is triggered every time a record is added to a table. This is the workflow:

2021-02-06 01_23_43-ERIS2 - AppSheet

The log shows no errors:

The expected behaviour is that a pdf is created. The behaviour in this case is that an blank 1kb sized PDF with the filename “.pdf” is created instead. It seems as if the virtual column Filename which depends on the id is using an blank id because the created filename is “.pdf”:

Could it be the id is not yet known when the workflow is triggered when using MySQL instead of Google spreadsheets as database? How to fix this?

When I click the test button in the workflow header the PDF is created with the right filename and the file size is also correct and everything work fine. So it seems that everything has been configured correctly.

Please contact support@appsheet.com for help with this.