If the post has been removed, you are unlikely to get an injunction unless it happens again in which case, you can then involve the police although after only 2 incidents, the police may not be that helpful. The court will only grant the injunction to stop something happening in the future generally, if there is a threat of it happening orYou can threaten it though.
My suggestion would be to get a solicitor to write to the culprit saying that if this happens again, the culprit will face a civil application to court for an injunction and an application for legal costs as well as complaint to the police with a view to having the culprit prosecuted under the Protection from Harassment Act.
Hopefully, the letter from a solicitor will do the trick.
If not, then either you or the solicitor makes the court application using court form N244 and N16A
What you need to do make notes as dates times and occurrences because it doesn’t have to be the same kind of incident to be actionable by the police. It could be an unwanted telephone call, and unwanted letter, and unwanted knock on the door, an unwanted Internet post,which together constitute harassment