Problem with pen tool Illustrator CC 2020 24.3

[#1]

I'm new to Illustrautor and working through some tutorials.  I have this problem with the pen tool and was hoping that somebody might put me straight please.  I have fig. 1 which I want to trace over with the pen tool.  However, when I start to select the underlying image gradually starts to disappear as is shown in fig. 2 which is preventing me from completing the selection.  Why is this happening and what can I do to stop it please?  Rather frustrating but I guess this is par of being a raw beginner.  

Thanking you in advance

Sister Sabina

[#2]

I'm new to Illustrautor and working through some tutorials.  I have this problem with the pen tool and was hoping that somebody might put me straight please.  I have fig. 1 which I want to trace over with the pen tool.  However, when I start to select the underlying image gradually starts to disappear as is shown in fig. 2 which is preventing me from completing the selection.  Why is this happening and what can I do to stop it please?  Rather frustrating but I guess this is par of being a raw beginner.  

Thanking you in advance

Sister Sabina

[#3]

The default pen has a white fill. Instead choose no fill ( small box with a red slash through it). 

[#4]

Larry, I am hoping this solved her problem. If it doesn't, I think there might be an issue with the latest release. I went to create a tutorial to visually show how to do this and my Illustrator is doing the same thing. I tried it on two other computers that haven't been updated and it works perfectly. hmm...

[#5]

@27Mitaka Did Larry's solution solve your problem?