Hello, I have a project with some similar aspects. My project is for writing INVOICES and QUOTES. I use a single panel with text boxes and an int "MODE" which I change from INVC to QUOT and back. I actually keep the same text boxes and change their content. I build a string for each line and save it in memory when I switch away from one mode and then restore the contents back into the boxes when I return to that mode.
As an alternative consider this:
Place your panel 2 in front of your panel 1. If panel 2 is NOT visible, then panel 1 will be visible. When you make panel 2 visible, it "covers" panel 1 which effectively makes it invisible. When panel 1 is not visible, it makes no difference whether to contents of the text boxes are cleared or not.