Proc Traj - 1 group model error

[SG1993]

Hi,

I am trying to estimate a one group model with quadratic trajectory controlling for time-varying and time-independent covariates, it is showing me an error which says "risk statement is only meaningful for model with groups >1". Is there a way to include time invariant covariates in a 1 group model? 

Kindly advise. 

[JosvanderVelden]

I believe I have seen a post in the past where runing with double byte character support (DBCS) solved an issue with proc traj.
Can you try to run the same code in SAS 9.4 session with DBCS support?