Javascript Console error

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If this is an XFA form you must use XFA JavaScript, which is completely different, and in a different document (if it is still available at all). I do not think flattening an XFA form is even possible. The form is designed to be filled, submitted, printed, and nothing else. 

I was unable to edit the post.

Please fine the input logic here:

var pdfFormField = this.getField('topmostSubform[0].Page1[0].Table1[0].Row1[0].f1_18[0]');

if(pdfFormField != null) {

pdfFormField.value = "test"

}