Unfortunately it's not me who wrote this, but a Korean acquaintance of mine, who taught me how to say "thank you" in Korean. So I don't really understand what you wrote, but I see the ni-da at the end as well and guess it means something like "thanks, you're welcome".
I've learnt the same in Chinese (with Hanzi), Japanese (in Hiragana I believe) and I think thai this day as well.