Hi Max Bonzulak,
We're sorry for the inconvenience this has caused you.
What is the current OS version of your Surface Book 2? Are you using just an adapter to extend the display of your Surface device to external monitor? Have you tried using a different cable to connect these devices?
To initially troubleshoot this issue, I'd like you to clear the display cache of your Surface device by following solution # 3 from this link>>https://support.microsoft.com/en-us/help/4023496/surface-troubleshoot-connecting-to-a-second-screen and please check if the adapter you're using is what Microsoft recommends.
Kind Regards,
Crest