Created a scene with text, image and buttons but disappeared after entering play mode

Hello there, I am a beginner at unity and have created a game using the learning pathways in Unity. I tried creating a canvas and having elements like text, background image and UI buttons on the screen and added a script to it as well. However, after entering the play mode, they disappered from heirarchy and I cannot retreive them back. Any suggestions would be helpful. Thanks :slight_smile: