CSA needs to do something as we are struggling

I put in a claim form regarding child maintanance from father of my children 3years ago, through CSA services.

I have not received a single payment since then and everytime i speak to CSA staff, i have been told that the father of my children still not responding to the letter they sent.

This man has remarried, and am a single woman providing for the children we have together. i belief CSA need to do somthing regarding this issues, am really struggling to provide for my children.