Hi Peps,
I am out of resources now. Everything is ok except for this,

I tried four ways
- 1 copy exact code from velo api
- 2 put onBeforeSave within Page.onReady
-3 put onBeforeSave within dataset.onReady
-4 put onBeforeSave within button.onClick
and code also work on the live site. It only show the error on my editor.
Some light here please?
Thanks,
DA