In order to comply with section 4c of article 125 of Regulation (EU) 1303/2013, on anti-fraud measures, the following channels of complaint are available:
https://www.antifrau.cat/ca/investigacio/denuncieu.html
http://www.igae.pap.hacienda.gob.es/sitios/igae/es-ES/snca/Paginas/ComunicacionSNCA.aspx