If you have court ordered visitation your ex husband is bound by the authority of the court to follow it.
Immediately, take written proof by petition to the judge to enforce the order and seek sanctions.
He can, as custodial parent, decide that a cell phone is not a proper thing for your daughter.
Your ex-husband cannot deny your court-ordered visitation rights as a punishment toward your children. If he denies your rights you must file a Petition for Rule to Show Cause with the Court and ask that he be held in contempt for wilfully failing to comply with the Court's Order/Judgment.
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