Why groovy rule for validation is not functioning properly ?

Summary:

We have an issue with the following Groovy rule validation command.

In the current rule, the validation command "isMissing" is not functioning for the "Description" member, which has a data type of "text" which gives the error message "Please enter high level description" even when we enter description. In contrast, it functions correctly for the "Amount" member, which has a data type of "currency" .We need to identify what might be missing in the rule.

DataGrid grid = operation.grid
GridIterator itr = grid.dataCellIterator('Number of resources')

itr.each
{
DataCell Unitprice = it.crossDimCell('Number of resources')
DataCell Highleveldescription = it.crossDimCell('Description')