A) Make sure you understand the responsibilities of the Consumer Ombudsman (StK)
and that the subject of the report
of you is within the scope of these powers (https://www.synigoroskatanaloti.gr/el/armodiotites & in particular article
4 Law 3297/2004, as applicable).
The STK has the authority and role of mediator between consumers and suppliers and does not impose sanctions. He is only responsible for cases that have arisen up to one year before the submission of the petition and for which no legal proceedings have been initiated.
Indicatively, the SC is not competent: for disputes between businesses, for disputes connected with the business, commercial or professional activity of the petitioner, for disputes from transactions for which no legal document has been issued, for cases related to the control of fuel, food and medicine prices or for alterations/forgery related to the above, for tax disputes and in general for civil disputes against public bodies , OTAs (Municipalities, Regions) etc.
B) Make sure it does not concern a company/professional based outside Greece, otherwise you can submit a report to the European Consumer Center (ECC) after taking into account the relevant conditions and powers of the ECC.
C) Contact the supplier in any convenient way, in order to raise the problem that concerns you and seek resolution and proceed with the report if the problem is not resolved within a reasonable time.