Can you still dispute an Apple Pay transaction completed through messages even if the number blocked you?

I’m looking to dispute a transaction I made through a number. I was trying to buy something and decided on split payment. It was $400 in total but I already paid $200. But, it was never charged through my cards because my bf sent it over from his apple pay to my apple. After backing out of the deal, the scammer blocked me on everything I used to contact them and when I try to dispute my transaction how apple says to do it, none of the options are showing? Can I still dispute it even after the blocked me? I have the transaction number and I have SS of our conversation as proof they scammed me.