Displays SS but not IRs


sometimes a code solved to the 1st order runs well and displays SS and IRs. Then I change the value of a parameter and either Dynare only reports the SS or sometimes it claims that it cannot find it.
Does anybody know why Dynare can report the SS but not IRs?
or is it that sometimes Dynare can report as SS what is not really the SS and that is the reason it breaks without reporting IRs and without reporting any error?

Many thanks

If you are using order=1, this should not happen. Could you provide an example?