Is this incorrect grammar?

I am not the greatest at grammar you may have noticed. However which is correct?

If referring to a person, say in this instance a female would you say the following about her nice handbag.

‘She has a nice handbag’.
‘They have a nice handbag’.

To me, they would imply a group of people? It is just a friend of mine never refers to him or her, but they. As he is quite good at grammar I would like to clear this up. (Which does at times confuse me, as I think he is talking about a group of people).

Thanks!