The problem may be related that you selected "Purchase Line" as origin but did not set any value for it.
Could you copy-paste the text of the expection here instead of using an image. It's easier for us to understand it.
From the screenshots and the docker pull date it seems you are using 5.8 series
|2021-03-12 11:53:16||pokoli||set||messageid: <1615546396.387081.A2ZBYOSGQ7G7AHPM.firstname.lastname@example.org>|
|2021-03-12 11:53:16||pokoli||set||recipients: + Marc|
|2021-03-12 11:53:16||pokoli||link||issue10186 messages|
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