If you want to get in touch with the merchant, you should be able to find their contact details on the merchant’s website, for example under "Contact us" or "Support" pages. Some merchants provide contact details in their terms and conditions for escalation. Alternatively, you may try to contact them through social media.
Please note that Adyen is not authorised to provide contact information of our merchants and we are unable to take any action on behalf of merchants on individual transactions.