Baby puts his arms and fingers in mouth and refuses pacifier- advice needed

Em

My baby boy is 9 weeks old. I wasn’t keen on pacifier in the beginning due to my fear that it will mess him with breastfeeding so I have introduced pacifier quite late, around 5,6 weeks. He didn’t like it that much so I wasn’t pushing him. But now I have a huge problem. He has started putting his arm and fingers in his mouth and is sucking them. He absolutely refuses pacifier. I am afraid that eventually he will start sucking his thumb and I really want to avoid that.

Any advice how to help him accept pacifier? I have tried various brands (Avent, Nuk, Mam) and I have tried putting some milk on it, but unfortunately nothing is helping🙈