Why does the output of N4sid model (output of system identification tool) is not working in simulink

I have estimated 'n4sid' model using System Identification Tool box and I saved this 'idss' type model into my currnet directory and loaded into Simulink file where i am analyzing the model. When i import this model into Simulink using a block called 'idmodel variable'and tested, results are not same as the results of 'compare' command in script file. I am sure, it is not because of initial conditions. Becuase i tried with the initial conditions which is given by 'compare' command. Also, if it is due to initial conditions, results must be same after it reaches steady state, but it is not same.

[Rajiv Singh]

The usual advice is to ensure that you are using the same input and initial conditions are those used during comparison. Otherwise it is difficult to say without looking at the model. You can send your model to me if you want; also indicate which version of MATLAB you are using.