Maybe try a few brands- my DD flat out refused a dummy until she was about... Actually I can't remember when but she did take one eventually and then would only ever take a particular type and brand. We never forced it and just gently offered it to her a few times a week in different moments- when she was wakeful, sleepy, playtime etc. we let her hold it, play with it, look at it. One night she was very sleepy, in the cradle hold in my arms, but wouldn't quite settle (she often cried before going to sleep) and I spontaneously offered the dummy and she took it. It took a few weeks of offering though.

That said lots of babies refuse a dummy point blank and will never take one.