Unity upscales UI

Hello,
I made all of the UI in simulator mode and not in game mode, but now the UI is upscaled different on every device. For example; This is how it looks on the Samsung Galaxy Note 20 Ultra 5G: https://ibb.co/FDFfyYL (This is how I want it to look) And this is how it looks on a Samsung Galaxy Note 10: https://ibb.co/Mp6ThKD
How can I fix this?

Quick question, is this using UI Toolkit or a uGUI Canvas?