A party can always file a post-judgment motion upon a showing of changed circumstances or to enforce a court order/judgment. It appears that your ex may be playing games and a formal schedule may be necessary to ensure that you have summer parenting time. A consultation with a good family attorney in your county may be a wise investment of time and effort as they can assist you in the process.
The above represents legal information and not legal advice nor a legal opinion of Bryan T. Eggert, Esquire. It is not intended to be relied upon by any person for any particular case. Nor does this information create an attorney-client relationship between the poster and the answering party. Whenever seeking legal advise, it is always advisable to consult privately with an attorney concerning your particular matter.