I'm trying to tell someone the reason I don't want to do something is because i barely know them. I'm not even sure if the verb I'm suppose to be using is 知る。I feel that might be really rude to say to someone. I searched around and the only word I can find that might work is なじむ(馴染む)。 I also don't know if I should use their name like Example : まだアリサさんになじまない = I'm not familiar with Alyssa yet.
なじむ is rarely used for a person, so まだアリサさんになじまない is unnatural.
I think 知る、親しくなる、仲良くなる are better like ～さんをよく知らない、～さんと親しくなっていない、～さんと仲良くなっていない.