@scottstephan
There are most likely many reasons for something like what you describe that could cause this, especially since you have not given me much to go on .
The first thing that I usually do though when something stops working when it worked before and I made no mods between the last time I closed Unity and the next time I open it is I first close Unity then I delete the “Library” folder in the project. Unity will rebuild the folder when it is re-opened. Many times this fixes the problem for me immediately.
Did you use “UnityEngine.UI” at the tops of the script?
Did you upgrade Unity? Maybe the sprites aren´t well positioned on the screen, specially when you hit play. The sprites on screen look different when you use the editor, and the play mode.
Hii,
I am not sure about your problem but incase you are using canvas,please check in properties the camera type. If its Screenspace overlay then all the sprites with go behind the UI.
Or
Check your camera properties —> Culling Mask. If “everything” is selected then something else is causing the problem.