Updating form with Form Generator

I have made an update form and it appears to work. I entered field values in the tabel with PhpMyAdmin, and the form will read the query. When I update fields through the form, that will work too.
BUT: when I refresh the formpage in Wappler it will completely wipe the record and set the fields to NULL.As far as I can tell everything is set as should, so (as usual) I don’t understand why this is happening.

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