Hey @material-specialist1
Welcome to the Postman Community 
I have tested with the following script and it seems to return an expected result 
const lodash = require('lodash')
const array = {
'abc': [
{'dc': 'example1',
'item': [
{'iCode': 1},
{'iCode': 2},
{'iCode': 3},
]},
{'dc': 'example2',
'item': [
{'iCode': 'a'},
{'iCode': 'b'},
{'iCode': 'c'},
]},
{'dc': 'example3',
'item': [
{'iCode': 'x'},
{'iCode': 'z'},
{'iCode': 'y'},
]}
]
}
pm.test('iCode are in sorted order', () => {
for (var i = 0; i < array.abc.length; i++) {
const itemArray = lodash.map(array.abc[i].item,'iCode')
const orderedItemArray = lodash.orderBy(itemArray)
pm.expect(itemArray).to.eql(orderedItemArray)
console.log(orderedItemArray)
}
})
Hope this helps! 