“Running my Mouth”

I have a guy friend who has always told me I constantly run my mouth. He can pick me on 24/7, make unnecessary comments, be mean but when I go to defend myself I’m suffering in the wrong for running my mouth. He says he’s joking around and he doesn’t know why I take him seriously but honestly I don’t know when he’s joking or not because he’s always the same. If I ever say something that’s a joke he gets all offended and acts like a brat pouting. I find it completely unfair that it’s ok for him to “joke” but when I do it I’m in the wrong and get told i constantly run my mouth. This causes legit arguments between us that typically resolve on their own over an hour or so but it really upsets me and I’ve told him this but he responds with “you’re being a Karen and getting so emotional”. I’m super frustrated because I don’t understand why it’s ok for him to do something but not anyone else and on top of that I feel like I just need to learn to ignore him but how when it upsets me so much?? Any advice.