How to reset dialog form after returning to data table in VueJs?

[behrouzbk]

I have create a VueJs page for adding and editing invoice data , I am using Vueify UI , the page has a data table of invoice data and a dialog form is for inserting(adding) and editing the head of invoice and also invoice items data.
After editing an invoice and it items, when I try to add a new invoice, the list of invoice items come to new dialog for adding new invoice.

My question is how I could reset the structure of invoice items and head before starting to add new invoice.