Not open project React native

Guys hello.

I change the project´s folder and after not workking the mobile simulator android.
please help me fix this error.

"To reload the app press "r"
To open developer menu press "d"

warn No apps connected. Sending "devMenu" to all React Native apps failed. Make sure your app is running in the simulator or on a phone connected via USB.
info Opening developer menu..."

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/1w8raqk6wrtzgnsgdrjm.png)