Why does my iPod screen pop out after replacement.

Hi, why does my iPod screen pop out after i replaced the LCD. I had problems with the homebutton and the LCD was broken so i replaced it (And it actually worked :3) There was a post about how to replace it, but now it wont close... I really need it closed because im giving it to a friend as gift. And last time i tried to get it in it almost cracked the screen (for pressing too hard) It works fine, the touch and everything, But it wont close.

Thanks for looking at this post :-)

I'm really happy for that, and i hope someone can help.

Regards Esben V