'Do' and 'does' are both equally forms with the current indefinite tense in the verb 'to complete.' Which one particular you may use will primarily rely on the sentence's topic. Their use is sort of equivalent, apart from a person instance where You should utilize 'do' and never 'does.' https://financefeeds.com/ifx-payments-selects-form3s-verification-of-payee-solution-ahead-of-eu-compliance-deadline/