Hausman test

[PENDO]

I need to run Hausman test in Error Correction model, but i am getting the error message which says that in order to run random effect model i must specify the dependent variable followed by a list of regressors. What i know is that the ECM has a system of equations by default where one variable in the form of first difference is a dependent variable followed by a list of regressors which are in the first difference format. May you please advice what night be a problem