Hi just 3 day and its today. . Thank you for your comment
If it were in your uterus when it split, it would mean you now have two embryos where one was, and if they both take, you will have identical twins (or more, if you had other embryos transferred at the same time and if they also take). But since it split while still in the petri dish, it simply means that you have one more available embryo for transfer.
It's all good news, because it gives you one more embryo's worth of chances to get pregnant. You can transfer one and freeze the other, or transfer both. (Interestingly, if you transferred only one and froze the other, you could later -- given successful transfers of both -- have identical twins born a certain amount of time apart.) Depending on what day the embryos split, there shouldn't be medical complications of them not splitting fully or anything like that. Are you doing a 3-day or 5-day transfer? The earlier the better, for splitting.