proc PHREG all of my coefficients are zero?

Hi All,
I am using proc PHREG to run a survival analysis and although I'm not getting any error messages, I'm pretty sure something is going wrong, because all of my chi-squared values and parameter estimates are coming out at exactly zero, no matter what model I run. Has anyone ever seen this before or have any idea what might be going wrong? I can get a very similar program to work on a different data set. Have posted my code below if needed.

*full model;

PROC PHREG DATA=Y_surv.Survival;
MODEL Duration*censored(0)=age bmiwk0 wt;
ARRAY time(*) time1-time4;
ARRAY w(*) wt1-wt4;
DO j=1 TO 4;
IF Duration > time[j] AND time[j] NE . THEN wt=w[j]-wt1;


*a more simple model;

PROC PHREG DATA=Y_surv.Survival;
MODEL Duration*censored(0)=age;



Point Mass at Zero
May be there were no failures in your data? Are all the censored values 0? (I am not sure this would be the reason, as the survival estimate should still be 1 if all the censored values are 0).