It’s not so much about the ever changing amount, somewhere between 3000 and 5000 according to the OP, but to put a stop to the possible scam in the first place. If no one complains they can do it again and again.
File a report.
Here too https://www.ocpb.go.th/ewtadmin/ewt/ocpb_en/ewt_news.php?nid=30 if appropriate.