Hello gm bos,
Sorry for late reply to this,
Do you mean that when you trying to publish a blog post then hitting this error right?
0 (#200) The user hasn't authorized the application to perform this action
If yes, first you should check back with your Facebook apps domain name is it set correctly after your webhosting changed your domain name.
Second, click revoke access link from your backend > Easyblog > Autopost > Facebook
Third, delete the Facebook apps from your Facebook > setting > apps > check my screenshot below.
Fourth, after you deleted, then you click "Sign in with Facebook" from your backend > Easyblog > Autopost > Facebook
And see how it goes?
If you need assistance, please provide us with your Facebook access as well.