How do you take someone out of a Facebook group message?

[colossalsail789]

I made a Facebook group message for my prom group but 2 people recently dropped out of the prom group so I was wondering how I could take them out of the group message

[Ali]

Hi dear.I think you may go to remove and remove them.But who dropped them out?!Somebody or themselves?I think there should be a rule for these!Good will.

[Unluckyscarecrow817]

they should automatically be gone from the group chat if they got dropped from the group but if they arent then they have to do it themselves by clicking on the "leave conversation" option