Error in executing On user input script

Error in executing On user input script

Tipo_list.addAll(Tipo_rec.Clase_credito.getall());
for each Clase_credito in Tipo_list
{
Tipo_credito:ui.add(Clase_credito)
}

Error in executing On User Input script of Periodo en años.

I'm having problems with this  this script :	;	Tipo_list=List(); Tipo_rec = Tabla_factores[Periodo == input.Periodo_anos.toLong()];
Error.
Error in executing Fetch Record task. Unable to fetch Tabla_factores and update variable Tipo_rec.
Error in evaluating the criteria :
Error.
Error evaluating NUMERIC expression Cpuld someone help me with this? Thanks bbogota