serverless-invoices/public/locales/en/invoice-header.json

{
  "invoice_title": "Invoice ",
  "invoice_number": "No.",
  "issued_at": "Issued at: ",
  "due_at": "Due at",
  "late_fee": "Late fee:",
  "add_late_fee": "Add late fee",
  "modal_issued_at_title": "Issued at"

}