fplot cutting off graph

I'm trying to plot the solutions to a differential equation (it's to teach us about QSSA for model reduction.) Every single one of my other plots have worked perfectly fine, except for this one.

The graph gets cut out for some reason, despite all the other fplots of the differential equations working perfectly fine. I checked the equations to see if there was some boundary issue but I found nothing.

Anyone else run into an issue like this? I suspect it's an issue with fplot or with the symbolic equation.

[Walter Roberson]

it thinks there is a discontinuity there. inf, nan, complex values might be present

[Scott Feltman]

Yes, I just looked at individual limits after the discontinuity and NaN appears for some reason. Thanks for the heads up