intellisense not working on vscode anymore

so i always used to work on vscode, and intellisense worked perfectly fine. but now suddenly, they on show monobehavior functions (like OnTriggerEnter) but don’t show GameObject, Rigidbody, etc… anymore. i tried uninstalling then installing extensions again, uninstalled and installed vscode, installed .net sdk, but nothing worked.

vscode editor in packet manager is installed and up to date, and preferences->external tools is set to vscode. how can i fix it?