Start by going back to the court who issued your order. Its hard to follow your facts, I'm not sure who you initially were in court with when you got the visitation ordered.
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You have to make requests regarding this matter in the Court that made the orders.
Yes, it appears he is violating the court orders. Since you have a phone number, you can give exparte notice to him. However, I would seek out a lawyer for this. Fight to see these kids, but make sure you have a lawyer to fight with you.
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