According to the judgment of the EU Court of Justice in case C-9/20 (Grundstücksgemeinschaft Kollaustraße 136), a taxpayer who applies the regular taxation procedure can deduct the input VAT only when he pays the invoice for the supply of goods or service to a supplier who applies the taxation procedure according to charged fees.
This is applicable since 01 December 2022.
The right to recognise input VAT has hereby been returned to the provisions of the "old" VAT Ordinance, which was valid until the entry of the Republic of Croatia into the EU on July 1, 2013, where it was clearly prescribed: if the delivery is made or an invoice is issued (marked R-2) by a taxpayer who applies the taxation procedure according to charged fees, the input VAT can be deducted only if the invoice is paid.
Look at what else we wrote about, maybe the answer to your question is already there.