Separation Agreement not filed after signed by both parties. Is agreement still valid?

I had my husband add that he agrees to make monthly payments until he has paid back all the monies he owes me. If I find out that he never actually filed the agreement to what ever office it is suppose to be given, can I still use my signed copy to show that he is in violation of the separation agreement? He stopped making payments. The Separation Agreement was submitted by my husband, not the court.