How do I get him to give me my dress back?

If I try going to his house he’ll call the cops on me. I broke up with him but he says he doesn’t care, he already has another girlfriend, and his mom is crazier than he is (and that’s saying something). He says he won’t give it back because he “thinks it a trap” and he’s “not stupid” but him acting like this is really showing how stupid he is

do you still have the receipt for the dress? considering who bought it though. also, idk if this helps maybe you could get one of his friends to hang out and try to idk figure a way that the dress is still present within the house and try to cope it back. usually when guys repeat that kind of language they don’t have anymore use of the dress(ex: selling lending etc) I have had it done twice,. I give you luck and hopefully the dress comes around.