Why is my cousin suddenly being distant

So for the past week he’s been texting me everyday all day and I spent the whole day yesterday with him and seen him nearly everyday suddenly it’s like he can’t be bothered with me he has hardly message me all day and when I asked him to call me he came up with an excuse that he will have his fone taken of him when he normally rings me every night anyways when I sed are u going to ur grandmas Tommorow he said he didn’t know and he would have to see why is he suddenly acting weird