Air conditioner still wont stay cold after compressor was replaced? Why?

What is your question?

Compressor was replaced, the air conditioning was charged and worked great for about a week, then it went back to blowing warm air? I have heat, that's working fine, but no air conditioning again?

How long has your 2006 Saturn Vue had this problem?

It was fixed twice by a mechanic he replaced the compressor but it still doesnt hold ac charge