Continuous Fibonacci Parametric Plot

[Rick314]

I am using the HP Prime Virtual Calculator v2.1.14425 (2020 1 16) Parametric App to attempt to plot the continuous Fibonacci parametric function (image 1). It has a complex result and I am trying to plot the RE and IM parts. As T goes from -9 to 9 the resulting complex-valued result should look like the last image below, produced with Derive for Windows version 5.06. Instead, for example with Trace on and T = 1.5, I get the "(NaN, NaN)" result shown. But it is close -- Jump to T = 6 and the correct real value (8,0) is shown (the 6th Fibonacci sum 1 1 2 3 5 *8*). Why isn't the desired plot shown by HP Prime?