GUI Issue referencing function file

I'm creating a GUI that references a function file that I have already made. The output of this file is [TAU, P] = solver(inputs....). When I run the function file in the workspace with valid inputs, it works great and I return the graphs I need. But creating this GUI, I have a button that plugs in user-inputs into all the variable fields and should return me two arrays, TAU and P, and plot them. Everything works outside the app designer, but for some reason the GUI won't recognize P as an output array? P is defined so I'm unsure as to why I'm getting this error.

Error from GUI after trying to plot

Tau is fine but P isn't?

Any help is gfreatly appreciated.

[Rahim Parvez]

I figured out the problem. No need to respond.