Visual Studio Code – How to stop Visual Studio 2022 to add namespace automatically after copy codes from other place

As the title said, now I have a problem when copy codes from anywhere, and when pasting to my source files (C#/.cs), it will add a namespace automatically, sometimes the namespace is wrong but I don’t know because it was added as unused namespace, but it will have a problem later when I build the project (with Unity) because it can’t find the namespace, Then I have to delete it, it is very annoying.