Due to GST (VAT) requirement in Malaysia, we need to change the word Invoice to Tax Invoice. Please find the snapshot here: [login to view URL]
We have contacted skyverge support and their reply as follows:
"You can use the wc_pip_document_heading filter to change the title of the invoice."
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=== WooCommerce Print Invoices/Packing Lists ===
Please quote for this customization.