So after 2 months (1.5 no contact) having come to terms with losing my ex to another guy, who she seems in love with, we are back working together.

I told her in the nicest possible way we cannot be friends. We are speaking briefly but there is a slight awkwardness. I have never felt lost for words around this girl and used to be able to neg the hell out of her for fun.

My head feels hesitant so can anyone advise how I can regain her attraction and flirt? negs? Just be polite? I dont want to fall in the friend zone yet dont want to be too forcefull