Matplotlib Problem Question

Greetings:

I have installed Matplotlib for graphing weather reading from a Sense-Hat atop a Raspberry Pi4 using Buster OS
My program calls up Matprolib via pyton3.7 and a Figure 1 box appears but no GRAPH.
When the Figure 1 box appears, whatever is behind the box on the screen appears in the box.
Has anyone seen this problem or know why this is happening???
Any advise would be greatly available.
Thanks in advance.!

Any chance you can drop in a screenshot or even a photo of your screen to show what’s happening?

Greetings:
Thanks for having a look at my problem.
I call up my program and the figure 1 - box appears but with screen background in the box.
I could not seem to get a screen shot on my raspberry pi4, so I took a photo.
I hope that that is visible to you as I tried to copy&paste it.
Any help would be greatly appreciated.
Thanks
Tom

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