不用了，谢谢。 和 不需要了，谢谢。 和有什么不一样？ | HiNative 不用了，谢谢。不用了 means you dont need the help 不需要了 means you dont need the help anymore They are NOT used interchangeably |There is no problem with your choice In my personal experience, I would say "我不抽烟，谢谢" in the situation 2, and "不用了，谢谢" in all other situations Both of "不用了" and "不需要了" can indicate a rejection of the offer
甭谢是什么意思？ -关于中文 (简体)（中文） | HiNative 甭谢you're walcome or No need to say thanks |甭の姿は“不”と“用”を合併されるというものだ。🤭|you're welcome|甭 = 不用 甭谢 = 不用谢 = 感謝の必要がありません = どういたしまして|I believe it's meant to be 不用谢=no problem you're welcome|A：ありがとうございます B：不用谢（いいえ、どういたしまして)的定