Father blocking phone call access to child from other parent

Q: I have a joint custody settlement created outside of court and signed by a judge in NYC family court. (We are regular folks with no legal issues, nor abuse against our son.) My child's father continually blocks my phone access to my 7yr old by turning his phone, his wife's phone, and my child's phone off on days he decides not to allow me access. (Days I drop my son at school and he is picked up by his father are days he thinks I should not "need" to talk to my son.) Nothing in our agreement specifies that I should not be allowed a short call with my son to say goodnight on these days. Also, my son and I enjoy speaking every day when he is at Dads, nothing excessive just one call. What are my options to enforce allowing my son and I to speak on these days which occur once or twice per wk?

A: David's Answer:  You'll need to file a modification petition asking for a provision allowing 1 call per day to each parent who does not have the child. Prescribe a time & have the provision state that the other parent is require to facilitate the call. -- David Bliven, Bronx Child Custody attorney (www.blivenlaw.net)