My ex hasn't seen his daughter over 2 months.?

His mother was the one that wants to see her. By the court order i leaglly do not have to let his mom or sister pck up my daughter. IS HE VIOLATING CORT ORDERS BY NOT SEEING HER OR CONTACTING ME ABOUT VISITIONS. ikeep calling him and askign him when he wants to tak her or i say to him want to take her th weekend and he says no. Then his mom asks him did ou tal to heather he said she wo't let use take her wheni never said.