25To accept that it is possible for Member States to exclude, in such a case, any reduction of the taxable amount for VAT purposes would run counter to the principle of the neutrality of VAT, which means, inter alia, that the trader, as tax collector on behalf of the State, is entirely to be relieved of the burden of tax due or paid in the course of his economic activities which are themselves subject to VAT (order of 24 October 2019, Porr Építési Kft., C‑292/19, not published, EU:C:2019:901, paragraph 23 and the case-law cited).