I am following this video: PowerApps Repeating Tables like InfoPath Part 1 - Enter the data
And I am trying to make PowerApps repeating tables like in example in video. I have blank Screen with a button that opens Screen- VaucherForm.
Blank screen with a button. Button value for OnSelect is:

And then in my screen VaucherForm, I have gallery form Form4 with sql table as datasource. There are a few text fields on form, and an icon to save data and create new line.
I got an error at icon for saving data.
OnSelect for Save Icon. Error on ThisItem:

Not sure what this error is trying me to do. There is a Account column in my datasource table, but why is it mad about that column?