Changing og:title of self hosted objects

Question

I'm currently working on a unity project and trying to implement custom stories in the same. I created a self hosted object. I want my og:title to change from unity code e.g. I want to have multiple titles as I cleared level one, I clear level two etc. Just not able to do it. Is it possible to do so?? I always get the og:title as declared in the meta property of the html page of that object. Please help.