An error occured on insert - No log

Hi All,

I have a simple table and I use grocery crud to manage it. When I try to insert a new row I get a pop-up with this text “an error occurred on insert”. Incredibly, there is no log reported on the Codeigniter application/log and no log reported in the browser console as in the following screenshot. Any idea? thanks.

And the logs of your web server that they throw or that you say or show.
The caption of each columns is missing
Units …
Languages …