DateTime field with picker

I am new to appgyver.

I am using backendless and I am trying to create an update form for a record where one of the fields is a date field. The form has about 20 fields. The datefield has a value in it already that the user may or may not want to change.

I don’t understand how to tie the datepicker to the field. I used the date picker page example. I can get the date into a page variable. But if I try to change a data variable and set the date field in the object properties, it resets the entire form. So I don’t know how to send the picked date to specific field.

Is there a tutorial I am missing? Thank you