Disable auto posting for some posts

[David]

Hello, there are some posts on my blog that I don’t want to mirror on my social networks accounts. So I would like to disable auto posting for these posts.
The problem is, the check boxes next to the social networks (Facebook, LinkedIn) are greyed out. If I click on them, nothing happens and they stay checked.
As a result the posts are sent to my social networks and then I have to manually delete them.
Why are these check boxes greyed out?
Thanks,
David

[Author]

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