Over time things wear out. Every time one opens a slip joint it wears on either one side or both of the joint as a natural consequence of use. Of course, it may leave the blade not centered. Throw the thing away and get a new one, or keep it and use it, your choice, I guess... Is it a tool or a jewel?
I'd like things to stay like new forever, but patina happens too and scratches from use and handle materials and etc. breakdown. Enjoy them? I do.