If the ID statement includes parameters from the PARMS statement, PROC NLIN will fail to converge.

In order to circumvent the problem, do not include parameters on the ID statement. Instead use the OUTPUT OUT= data set with the PARMS= option. It is important to list the parameters on the PARMS= option in the exact same order as they appear in the table of parameter estimates. This will also be the order that they appear in the PROC NLIN step.