Run ( random parameter ordered probit model )

I used an ordered probit model for analysis and I used ViF to solve the multicollinearity finally I used Backward method to remove insignificant variables. I had good results but the reviewers asked me to address the unobserved heterogeneity. I tried to run this model in STATA but I can't. So I need someone to use my data and choose the most suitable regression for my data ( RUN RANDOM PARAMETER ORDERED PROBIT MODEL )