I let a friend of mine use my sax a few days ago. They didn't have any experience but they wanted to play. The day after my sax wouldn't play anything but a few notes. I have found that my middle A key will not close all the way, but if I press on it really hard it will close and I can pretty much play all the notes. My middle G is just sorta hard to control. Please help if you have an idea. I'm not sure if this is from lending my sax because I was sitting next to them, but I've learned my lesson!