DOKU is a PSP company that is obliged to pay tax to the Indonesian Government. DOKU will send a Tax Invoice (Faktur Pajak) for every issued invoice. Tax Invoice is proof that DOKU has charged VAT to Merchants.
Therefore, Merchants do not need to pay the Tax Invoice as it is included in the Invoice.
In Indonesia, the value-added tax, also known as PPN (Pajak Pertambahan Nilai), is set at a rate of 11% on top of the fees incurred to process the transaction.