What version of Premiere Elements are you using and on what computer operating system is it running?
How did you apply the pan and zoom effect to your video? Please confirm that we are discussing pan and zoom effect applied to a video file and not a still.
a. Pan and Zoom Tool
b. Effects/Preset and one of the horizontal or vertical pan or zoom.
c. Keyframing the Scale property (for Zoom) and Position property (for Pan)?
With regard to "c"...if your clip is selected and you are in Properties Palette/Motion Panel expanded (Premiere Elements 10 and earlier) or Applied Effects Tab/Applied Effects Palette/Motion Panel expanded (Premiere Elements 11, 12, 13), is the Toggle Animation tab highlighted? Depending on your details, we could click on that and confirm that you want to remove keyframe(s) from the clip.
View from Premiere Elements 13 Applied Effects Tab/Applied Effects Palette/Motion Panel expanded....showing Toggle animation is the selected state.
We will be watching for your details to help us help you.