Thank you for your message and welcome to the TeamViewer Community! 🙌
macOS 11 Big Sur is not officially supported yet. Therefore, there still can be issues/bugs when using TeamViewer with this OS.
You will find all the information you need regarding officially supported OS in our Knowledge Base article here: Compatibility with macOS
Our dedicated team is currently working on it and we put our efforts together to officially support macOS 11 Big Sur as soon as possible.
We are sorry for the inconveniences caused.
I'd be grateful to test a beta. I have worked in IT for many years and would be happy to provide feedback.