It is absolutely okay to address a girl/ a lady as Miss, and we use it a lot, though it do has two meanings in China. One meaning is the form of address for ladies, another one is the job title of prostitutes. But based on the occasion and the attitude of the speaker, people won't get wrong about the meaning. So don't get wrong about that Chinese person‘s explanation, Miss is widely used as a normal address for ladies, at least in all the cities i live and lived in China.

Well, if you mean to ADDRESS someone, then 小姐 is technically a young woman. No other conotations. In Mainland, depending on the context, 小姐 can be a young woman, or a prostitute. It's hard to generalize. Specifically, With a family name ahead, 小姐 is used to address a young woman. eg, 王小姐 is Miss Wang. 小姐 is very likely to mean a prostitute when it is preceded by 找, ie 找小姐, which means to look for a prostitute. If you are worried, you may use other words: 美女、姑娘、姐、小妹、师傅、同志。 Or simply start the conversation with 你好，请问……

It's ok to call women as 小姐 in Taiwan, but if you say that word in mainland China, that sounds like bitch. In mainland China, it's a good idea to say 姑娘. But it doesn't work in Taiwan. It's a little out of date to Taiwanese people.

谢谢!

You can call a young girl “小姐姐” without her last name. This words “小姐姐” is very popular in younger Chinese recently.