Welfare IRFs problem

I would like to know what I should do to obtain welfare IRF=1. When I set order=2 and run dynare I have this error message:
Error using set
Bad property value found.
Object Name : axes
Property Name : 'XLim’
Values must be increasing and non-NaN.

but for IRF=2 and more, it works correctly.

Also, how can I interpret the Y axis or have I to look at the sign only.

It seems Dynare does not allow to compute IRFs for only 1 period. Please use at least two periods. What do you mean with how to interpret the Y axis? The Y axs depicts the units in which the respective variable is measured.

when IRF=2, I obtain a figure with only one period at the second order. Is that acceptable?

There should be two periods, the impact period and one after that.