Hey there,
If I understand your note correctly, do you mean that to unlike they need to click the Like button twice?
If yes, I would like to explain something to you regarding this.
1. For users that haven't like, if they wish to unlike it and follow the instruction of your note to do it, it will be the same remain nothing happened. This is because when the first time they click the Like button, it will be liked. But when the second time they click the Like button, it will be nothing happened back.
2. For users that have liked it already, if they wish to unlike it and follow the instruction of your note to do it, it will be the same remain liked. This is because when the first time they click the Like button, it will be unliked. But when the second time they click the Like button, it will be liked back.
In my opinion, I don't see there is any logic to do this. For example Facebook, it does not have an unlike button to let users press too.
If the users really wish to unlike the stream item, they can just ignore it and don't touch the reaction button.