Unable to make HypoTestPlot for every point


I have a problem looking at HypoTestPlots produced by RooStats HypoTestInverter class.
I have run as usual HypoTestInverter and I have produced a rootfile where I stored the Result.

In principle I should be able to make a plot for each scanned point, but this time I can plot just the first 3 points. In all the other cases I get:

[#0] ERROR:InputArguments -- RooAbsRealLValue::frame(xaxis) ERROR: open ended fit range, must specify plot range
[#0] ERROR:InputArguments -- invalid variable to plot

(even if -apparently- the HypoTestInverterResult plot makes sense)
You can find attached the rootfile containing the Result and the macro I have used.

Thank you.

Freq_Cls+b_grid_ts2_ToTest.root (2 MB)
PlotSingle.C (759 Bytes)