iMessages not syncing across iPhone, Mac, and iPad

My MacBook and iPad don't sync with the same settings as my iPhone. When I delete a message on my iPhone, it doesn't carry over to my Mac and iPad. However, if I delete a message on my iPad, it only deletes from my Mac and iPad, leaving my iPhone with the message still intact. I can send and receive messages, but when it comes to deleting messages, it doesn't work properly. Any assistance?

[Re-Titled by Moderator]

Original Title: iMessages Syncing