If you have added or changed contact information -by editing said contact of a client you have already invoiced (or supplier you used to add a bill), you can transfer the change on the document by following these simple steps:
#1 On the invoice overview page, click 'edit'.
#2 From the invoice edit page, select "client details"
#3 Hit the re-fetch from contacts button on the bottom of the'client details' card.
Click 'OK' for the changes to apply.