Suggest A Sleeping Aid That Can Be Taken With Ambien

I am suffering from severe insomnia. I have been taking Femara for several years, and the problem is getting worse. I was finally prescribed Ambien (10 mg); it worked for a while, but it is no longer helping me. I am so tired from not sleeping that I am afraid I am going to get ill. Is there anything I can take with the Ambien to help it work better for me.