change my iMessage account on Mac
I use my mums iCloud Apple ID account for everything except messages, so when setting up my MacBook Air computer I logged in with her Apple ID. although, it automatically logged me in to her messages account as well. I can't find any messages icon in the settings to change the Apple ID for just messages. I even sign completely out of her Apple ID and signed in with my own but it still kept her messages any ideas what I could do?
MacBook Air (2018 or later)