@Giovanni ***************
your first mistake was believing anything a thai embassy says about entering the country on a visa exempt entry ๐ฎ as James said, you CAN get one 30 day extension on a 30 day visa exempt entry at the immigration office for 1900baht.
If you're wanting to come in to the country visa exempt, forget what the embassy is telling you, don't worry about the requirements for a tourist visa and just apply for a thai pass, meet the entry requirements and come in on a 30 day visa exempt entry stamp