got turned away at a beach in Thailand, ranger said no drones anywhere on the island??

ok so this was frustrating. did all my research before the trip, checked the CAAT website (thai aviation authority), my drone is registered and i have the whole app on my phone showing green zones. fly to Koh Lanta, get to the beach, set up, and this local park ranger comes over and just says no drones allowed on the whole island. no sign, nothing posted anywhere, he just said its a rule.

i didnt argue because obviously not worth it in a foreign country but im still not sure if he was right or just didnt want to deal with it. anyone dealt with this kind of thing where the local rules seem to be different from what the national authority says? it felt like he was making it up but maybe there are local bylaws or something i missed