Hello, I've recently purchased a Casio fx-CG 20 calculator but after a few minutes of using it, I started getting an error everytime I tried to draw a graph using the regular graph feature. I've followed the manual plenty of times and tried using different types of graph functions, but each time I draw the graph I recieve an "Invalid Type" error. This error only occurs on the regular graph feature as the dynamic graph and conic graphs features work with no such problems.
This is a constant error and occurs no matter what function I enter to draw. I've tried resetting the calculator and its setting plenty of times but the error keeps occuring.
Any help will be appreciated.