What would you do if your maid lied about having no bf when she actually has.

If I were in your shoes, I would sit her down and let her know that I am aware that she is in a relationship. Try to find out the reason why she felt the need to lie and address those concerns. Next, I would stress that as long as her work is not affected (e.g., not spending excessive amount of time on the phone, going out during working hours), she can spend her free time however she likes. Also, I agree with setting boundaries such as not having her boyfriend over in the house, coming back before a certain time on her off day. The most important thing, I feel, would be to find out the underlying reason for lying so that her concerns could be addressed. This will help build trust between you and her. Good luck!