How to include .dat file while writing a code in cplex opl using main function?

I am trying to solve an iterative optimization problem in cplex opl using main function. The optimization objective and constraints are written in subvaluenew.mod.

float maxOfx = ...;
dvar float x;
int z=...;
maximize x+z;
subject to {
  x<=maxOfx;
}

execute
{
writeln("x= ",x);
}

and the main script is written in examplenew.mod file.

main {
      var source = new IloOplModelSource("subvaluenew.mod");
      var cplex = new IloCplex();
      var def = new IloOplModelDefinition(source);
     
     
     
      for(var k=1;k<=10;k++)
      {
      var opl = new IloOplModel(def,cplex);
      var data = new IloOplDataSource("examplenew.dat");
      var data2= new IloOplDataElements();
      data2.maxOfx=k;
      opl.addDataSource(data2);
      opl.generate();

      if (cplex.solve()) {  
         opl.postProcess();
         writeln("OBJ = " + cplex.getObjValue());
      } else {
         writeln("No solution");
      }
     opl.end();
    }  
     
    }

One of the parameter that is used in objective function is read from the excel file in examplenew.dat file.

SheetConnection Data("C:\\Users\\subha\\Downloads\\rk.xlsx");
 z from SheetRead (Data, "sheet3!F18:F18");

I am getting error in this code. If I have to use the .dat file to load the parameter data, how can I eliminate this error. The error showing is : data element z is not defined. However, I am defining the parameter z in subvaluenew.mod file. Please help me in solving this error.

In the main model

opl.addDataSource(data);

Is missing