I have facebook messenger application (it is bot using MS Bot Framework, although I don't think it is relevant). It has webhook subscribed to page events. It used to work fine until few days ago, when the webhook was unsubscribed from page and when I am trying to subscribe again it tells me:

> 
> "Insufficient Permission You do not have the necessary permission for
>  the specified Page to perform the requested action."
> 
> 
> 

I am owner and admin on both the FB page and messenger app. I created similar page and messenger app and it works there, but I still need to use this old one. I tried subscribing to other pages which I own and admin, but with same result. I also tried it with other person who is admin. 

I found other people experiencing same/similar message on FB, but not in this particular case. But I haven't found any solution. 

Does anyone know what could be the problem? Or have anyone experienced this issue? 

Thanks in advance for any ideas.