Thank you!= 고마워요, 감사합니다!🥰
You're welcome!= 천만에요???😳

Most Korean

language book introduce 'You're welcome!= 천만에요'. But as for me, I haven't used '천만에요' at all. Furthermore, I've never heard someone say '천만에요'. Just for sure, today I asked my colleague
"Have you ever said '천만에요' in responce to an gratitude?" He asked me back "천만에요?? Is it just written in books? It's too old fashioned. I never been used it" "I'm telling you. Why do all of Korean books translate 'You're welcome' as '천만에요'? What is the meaning of this word?"

천만에요(千萬에요) literally means 'There is no possibility of a thousandth(천千)or ten thousandth(만萬) of one' in other words, "Absolutely no! Never"
I can rarely use this '천만에' when I deny sth strongly. For example,
"Did I lie to you??" "천만에(Never!!) I always say the truth"

Then, when Koreans heard '고마워요' how they respond it?(in order of frequency of use)

1. Just "네~"😄(smile means 'It's my pleasure')
2. "아니에요/뭘요"(It was nothing, No problem)
3. "별 말씀을 (다 하세요)"(Don't mention it, It's not a big deal)
4. "아유, 제가 더 감사하죠"(Ah, I thank you more!)

Have you heard any Korean saying "천만에요" from TV drama/ Movies or real life?😉

한국분들에게: 혹시 '감사합니다'에 대한 대답으로 '천만에요'를 말해 본 적이 있으세요? 저도 궁금하네요ㅎㅎ